<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<xsd:schema attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://www.helixesg.com/20151231" xmlns:hlx="http://www.helixesg.com/20151231" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <xsd:import namespace="http://fasb.org/us-gaap/2015-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd" />
  <xsd:import namespace="http://fasb.org/us-roles/2015-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2015/elts/us-roles-2015-01-31.xsd" />
  <xsd:import namespace="http://fasb.org/us-types/2015-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2015/elts/us-types-2015-01-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/arcrole/fact-explanatoryFact" schemaLocation="http://www.xbrl.org/lrr/arcrole/factExplanatory-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/country/2013-01-31" schemaLocation="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/currency/2014-01-31" schemaLocation="http://xbrl.sec.gov/currency/2014/currency-2014-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2014-01-31" schemaLocation="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/exch/2015-01-31" schemaLocation="http://xbrl.sec.gov/exch/2015/exch-2015-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/invest/2013-01-31" schemaLocation="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/naics/2011-01-31" schemaLocation="http://xbrl.sec.gov/naics/2011/naics-2011-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/sic/2011-01-31" schemaLocation="http://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/stpr/2011-01-31" schemaLocation="http://xbrl.sec.gov/stpr/2011/stpr-2011-01-31.xsd" />
  <xsd:annotation>
    <xsd:appinfo>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="hlx-20151231_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="hlx-20151231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="hlx-20151231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="hlx-20151231_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:type="simple" />
      <link:roleType id="AllowanceAccounts" roleURI="http://www.helixesg.com/role/AllowanceAccounts">
        <link:definition>2120100 - Disclosure - Allowance Accounts</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AllowanceAccountsNarrativeDetails" roleURI="http://www.helixesg.com/role/AllowanceAccountsNarrativeDetails">
        <link:definition>2420403 - Disclosure - Allowance Accounts - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AllowanceAccountsSummaryOfActivityInValuationAccountsDetails" roleURI="http://www.helixesg.com/role/AllowanceAccountsSummaryOfActivityInValuationAccountsDetails">
        <link:definition>2420402 - Disclosure - Allowance Accounts - Summary of Activity in Valuation Accounts (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AllowanceAccountsTables" roleURI="http://www.helixesg.com/role/AllowanceAccountsTables">
        <link:definition>2320301 - Disclosure - Allowance Accounts (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessSegmentInformation" roleURI="http://www.helixesg.com/role/BusinessSegmentInformation">
        <link:definition>2114100 - Disclosure - Business Segment Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessSegmentInformationNarrativeDetails" roleURI="http://www.helixesg.com/role/BusinessSegmentInformationNarrativeDetails">
        <link:definition>2414402 - Disclosure - Business Segment Information - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessSegmentInformationPropertyPlantAndEquipmentNetOfDepreciationByGeographicRegionDetails" roleURI="http://www.helixesg.com/role/BusinessSegmentInformationPropertyPlantAndEquipmentNetOfDepreciationByGeographicRegionDetails">
        <link:definition>2414406 - Disclosure - Business Segment Information - Property, Plant and Equipment Net of Depreciation by Geographic Region (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessSegmentInformationRevenueByGeographicalRegionDetails" roleURI="http://www.helixesg.com/role/BusinessSegmentInformationRevenueByGeographicalRegionDetails">
        <link:definition>2414405 - Disclosure - Business Segment Information - Revenue by Geographical Region (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessSegmentInformationSummaryOfFinancialDataBySegmentDetails" roleURI="http://www.helixesg.com/role/BusinessSegmentInformationSummaryOfFinancialDataBySegmentDetails">
        <link:definition>2414403 - Disclosure - Business Segment Information - Summary of Financial Data by Segment (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessSegmentInformationSummaryOfIntercompanySegmentRevenuesDetails" roleURI="http://www.helixesg.com/role/BusinessSegmentInformationSummaryOfIntercompanySegmentRevenuesDetails">
        <link:definition>2414404 - Disclosure - Business Segment Information - Summary of Intercompany Segment Revenues (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="BusinessSegmentInformationTables" roleURI="http://www.helixesg.com/role/BusinessSegmentInformationTables">
        <link:definition>2314301 - Disclosure - Business Segment Information (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesAndOtherMatters" roleURI="http://www.helixesg.com/role/CommitmentsAndContingenciesAndOtherMatters">
        <link:definition>2115100 - Disclosure - Commitments and Contingencies and Other Matters</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesAndOtherMattersLeaseCommitmentsDetails" roleURI="http://www.helixesg.com/role/CommitmentsAndContingenciesAndOtherMattersLeaseCommitmentsDetails">
        <link:definition>2415403 - Disclosure - Commitments and Contingencies and Other Matters - Lease Commitments (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesAndOtherMattersNarrativeDetails" roleURI="http://www.helixesg.com/role/CommitmentsAndContingenciesAndOtherMattersNarrativeDetails">
        <link:definition>2415402 - Disclosure - Commitments and Contingencies and Other Matters - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsAndContingenciesAndOtherMattersTables" roleURI="http://www.helixesg.com/role/CommitmentsAndContingenciesAndOtherMattersTables">
        <link:definition>2315301 - Disclosure - Commitments and Contingencies and Other Matters (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedBalanceSheets" roleURI="http://www.helixesg.com/role/ConsolidatedBalanceSheets">
        <link:definition>1001000 - Statement - Consolidated Balance Sheets</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedBalanceSheetsParenthetical" roleURI="http://www.helixesg.com/role/ConsolidatedBalanceSheetsParenthetical">
        <link:definition>1001501 - Statement - Consolidated Balance Sheets (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfCashFlows" roleURI="http://www.helixesg.com/role/ConsolidatedStatementsOfCashFlows">
        <link:definition>1005000 - Statement - Consolidated Statements of Cash Flows</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfComprehensiveIncomeLoss" roleURI="http://www.helixesg.com/role/ConsolidatedStatementsOfComprehensiveIncomeLoss">
        <link:definition>1003000 - Statement - Consolidated Statements of Comprehensive Income (Loss)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfOperations" roleURI="http://www.helixesg.com/role/ConsolidatedStatementsOfOperations">
        <link:definition>1002000 - Statement - Consolidated Statements of Operations</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfShareholdersEquity" roleURI="http://www.helixesg.com/role/ConsolidatedStatementsOfShareholdersEquity">
        <link:definition>1004000 - Statement - Consolidated Statements of Shareholders' Equity</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsAndHedgingActivities" roleURI="http://www.helixesg.com/role/DerivativeInstrumentsAndHedgingActivities">
        <link:definition>2122100 - Disclosure - Derivative Instruments and Hedging Activities</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsAndHedgingActivitiesDerivativesDesignatedAsHedgingInstrumentsDetails" roleURI="http://www.helixesg.com/role/DerivativeInstrumentsAndHedgingActivitiesDerivativesDesignatedAsHedgingInstrumentsDetails">
        <link:definition>2422402 - Disclosure - Derivative Instruments and Hedging Activities - Derivatives Designated as Hedging Instruments (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsAndHedgingActivitiesDerivativesNotDesignatedAsHedgingInstrumentsDetails" roleURI="http://www.helixesg.com/role/DerivativeInstrumentsAndHedgingActivitiesDerivativesNotDesignatedAsHedgingInstrumentsDetails">
        <link:definition>2422403 - Disclosure - Derivative Instruments and Hedging Activities - Derivatives Not Designated as Hedging Instruments (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsAndHedgingActivitiesImpactOfDerivativeInstrumentsOnAccumulatedComprehensiveIncomeLossDetails" roleURI="http://www.helixesg.com/role/DerivativeInstrumentsAndHedgingActivitiesImpactOfDerivativeInstrumentsOnAccumulatedComprehensiveIncomeLossDetails">
        <link:definition>2422405 - Disclosure - Derivative Instruments and Hedging Activities - Impact of Derivative Instruments on Accumulated Comprehensive Income (Loss) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsAndHedgingActivitiesImpactOfNonDesignatedDerivativeInstrumentsOnIncomeStatementDetails" roleURI="http://www.helixesg.com/role/DerivativeInstrumentsAndHedgingActivitiesImpactOfNonDesignatedDerivativeInstrumentsOnIncomeStatementDetails">
        <link:definition>2422407 - Disclosure - Derivative Instruments and Hedging Activities - Impact of Non Designated Derivative Instruments on Income Statement (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsAndHedgingActivitiesLossReclassifiedFromAccumulatedOciIntoEarningsDetails" roleURI="http://www.helixesg.com/role/DerivativeInstrumentsAndHedgingActivitiesLossReclassifiedFromAccumulatedOciIntoEarningsDetails">
        <link:definition>2422406 - Disclosure - Derivative Instruments and Hedging Activities - Loss Reclassified from Accumulated OCI into Earnings (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsAndHedgingActivitiesNarrativeDetails" roleURI="http://www.helixesg.com/role/DerivativeInstrumentsAndHedgingActivitiesNarrativeDetails">
        <link:definition>2422404 - Disclosure - Derivative Instruments and Hedging Activities - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsAndHedgingActivitiesTables" roleURI="http://www.helixesg.com/role/DerivativeInstrumentsAndHedgingActivitiesTables">
        <link:definition>2322301 - Disclosure - Derivative Instruments and Hedging Activities (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DetailsOfCertainAccounts" roleURI="http://www.helixesg.com/role/DetailsOfCertainAccounts">
        <link:definition>2103100 - Disclosure - Details of Certain Accounts</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DetailsOfCertainAccountsAccruedLiabilitiesDetails" roleURI="http://www.helixesg.com/role/DetailsOfCertainAccountsAccruedLiabilitiesDetails">
        <link:definition>2403404 - Disclosure - Details of Certain Accounts - Accrued Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DetailsOfCertainAccountsOtherAssetsNetDetails" roleURI="http://www.helixesg.com/role/DetailsOfCertainAccountsOtherAssetsNetDetails">
        <link:definition>2403403 - Disclosure - Details of Certain Accounts - Other Assets, Net (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DetailsOfCertainAccountsOtherCurrentAssetsDetails" roleURI="http://www.helixesg.com/role/DetailsOfCertainAccountsOtherCurrentAssetsDetails">
        <link:definition>2403402 - Disclosure - Details of Certain Accounts - Other Current Assets (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DetailsOfCertainAccountsOtherNonCurrentLiabilitiesDetails" roleURI="http://www.helixesg.com/role/DetailsOfCertainAccountsOtherNonCurrentLiabilitiesDetails">
        <link:definition>2403405 - Disclosure - Details of Certain Accounts - Other Non-current Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DetailsOfCertainAccountsTables" roleURI="http://www.helixesg.com/role/DetailsOfCertainAccountsTables">
        <link:definition>2303301 - Disclosure - Details of Certain Accounts (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DocumentAndEntityInformation" roleURI="http://www.helixesg.com/role/DocumentAndEntityInformation">
        <link:definition>0001000 - Document - Document and Entity Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EarningsPerShare" roleURI="http://www.helixesg.com/role/EarningsPerShare">
        <link:definition>2112100 - Disclosure - Earnings Per Share</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EarningsPerShareComputationOfBasicAndDilutedEpsDetails" roleURI="http://www.helixesg.com/role/EarningsPerShareComputationOfBasicAndDilutedEpsDetails">
        <link:definition>2412402 - Disclosure - Earnings Per Share - Computation of Basic and Diluted EPS (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EarningsPerShareExcludedSecuritiesOnDilutedSharesCalculationDetails" roleURI="http://www.helixesg.com/role/EarningsPerShareExcludedSecuritiesOnDilutedSharesCalculationDetails">
        <link:definition>2412403 - Disclosure - Earnings Per Share - Excluded Securities On Diluted Shares Calculation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EarningsPerShareNarrativeDetails" roleURI="http://www.helixesg.com/role/EarningsPerShareNarrativeDetails">
        <link:definition>2412404 - Disclosure - Earnings Per Share - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EarningsPerShareTables" roleURI="http://www.helixesg.com/role/EarningsPerShareTables">
        <link:definition>2312301 - Disclosure - Earnings Per Share (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlans" roleURI="http://www.helixesg.com/role/EmployeeBenefitPlans">
        <link:definition>2113100 - Disclosure - Employee Benefit Plans</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlansNarrativeDetails" roleURI="http://www.helixesg.com/role/EmployeeBenefitPlansNarrativeDetails">
        <link:definition>2413402 - Disclosure - Employee Benefit Plans - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlansRestrictedSharesGrantedDetails" roleURI="http://www.helixesg.com/role/EmployeeBenefitPlansRestrictedSharesGrantedDetails">
        <link:definition>2413403 - Disclosure - Employee Benefit Plans - Restricted Shares Granted (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlansScheduleOfRestrictedStockAndRestrictedStockUnitsActivityDetails" roleURI="http://www.helixesg.com/role/EmployeeBenefitPlansScheduleOfRestrictedStockAndRestrictedStockUnitsActivityDetails">
        <link:definition>2413404 - Disclosure - Employee Benefit Plans - Schedule of Restricted Stock and Restricted Stock Units Activity (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EmployeeBenefitPlansTables" roleURI="http://www.helixesg.com/role/EmployeeBenefitPlansTables">
        <link:definition>2313301 - Disclosure - Employee Benefit Plans (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EquityInvestments" roleURI="http://www.helixesg.com/role/EquityInvestments">
        <link:definition>2105100 - Disclosure - Equity Investments</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EquityInvestmentsDistributionsFromEquityInvestmentDetails" roleURI="http://www.helixesg.com/role/EquityInvestmentsDistributionsFromEquityInvestmentDetails">
        <link:definition>2405403 - Disclosure - Equity Investments - Distributions from Equity Investment (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EquityInvestmentsNarrativeDetails" roleURI="http://www.helixesg.com/role/EquityInvestmentsNarrativeDetails">
        <link:definition>2405402 - Disclosure - Equity Investments - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EquityInvestmentsSummarizedFinancialInformationDetails" roleURI="http://www.helixesg.com/role/EquityInvestmentsSummarizedFinancialInformationDetails">
        <link:definition>2405404 - Disclosure - Equity Investments - Summarized Financial Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="EquityInvestmentsTables" roleURI="http://www.helixesg.com/role/EquityInvestmentsTables">
        <link:definition>2305301 - Disclosure - Equity Investments (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurements" roleURI="http://www.helixesg.com/role/FairValueMeasurements">
        <link:definition>2121100 - Disclosure - Fair Value Measurements</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurementsAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisDetails" roleURI="http://www.helixesg.com/role/FairValueMeasurementsAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisDetails">
        <link:definition>2421402 - Disclosure - Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurementsCarryingValuesAndEstimatedFairValuesOfLongTermDebtDetails" roleURI="http://www.helixesg.com/role/FairValueMeasurementsCarryingValuesAndEstimatedFairValuesOfLongTermDebtDetails">
        <link:definition>2421403 - Disclosure - Fair Value Measurements - Carrying Values and Estimated Fair Values of Long-Term Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurementsTables" roleURI="http://www.helixesg.com/role/FairValueMeasurementsTables">
        <link:definition>2321301 - Disclosure - Fair Value Measurements (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="Goodwill" roleURI="http://www.helixesg.com/role/Goodwill">
        <link:definition>2107100 - Disclosure - Goodwill</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillDetails" roleURI="http://www.helixesg.com/role/GoodwillDetails">
        <link:definition>2407402 - Disclosure - Goodwill (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillTables" roleURI="http://www.helixesg.com/role/GoodwillTables">
        <link:definition>2307301 - Disclosure - Goodwill (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxes" roleURI="http://www.helixesg.com/role/IncomeTaxes">
        <link:definition>2109100 - Disclosure - Income Taxes</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesNarrativeDetails" roleURI="http://www.helixesg.com/role/IncomeTaxesNarrativeDetails">
        <link:definition>2409405 - Disclosure - Income Taxes - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesReconciliationOfBeginningAndEndingAmountOfUnrecognizedTaxBenefitsDetails" roleURI="http://www.helixesg.com/role/IncomeTaxesReconciliationOfBeginningAndEndingAmountOfUnrecognizedTaxBenefitsDetails">
        <link:definition>2409408 - Disclosure - Income Taxes - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfComponentsOfIncomeLossBeforeIncomeTaxesDetails" roleURI="http://www.helixesg.com/role/IncomeTaxesScheduleOfComponentsOfIncomeLossBeforeIncomeTaxesDetails">
        <link:definition>2409404 - Disclosure - Income Taxes - Schedule of Components of Income (Loss) Before Income Taxes (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfComponentsOfIncomeTaxProvisionBenefitByJurisdictionDetails" roleURI="http://www.helixesg.com/role/IncomeTaxesScheduleOfComponentsOfIncomeTaxProvisionBenefitByJurisdictionDetails">
        <link:definition>2409403 - Disclosure - Income Taxes - Schedule of Components of Income Tax Provision (Benefit) by Jurisdiction (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfComponentsOfIncomeTaxProvisionBenefitDetails" roleURI="http://www.helixesg.com/role/IncomeTaxesScheduleOfComponentsOfIncomeTaxProvisionBenefitDetails">
        <link:definition>2409402 - Disclosure - Income Taxes - Schedule of Components of Income Tax Provision (Benefit) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetails" roleURI="http://www.helixesg.com/role/IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetails">
        <link:definition>2409407 - Disclosure - Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetailsCalc2" roleURI="http://www.helixesg.com/role/IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetailsCalc2">
        <link:definition>2409407 - Disclosure - Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesScheduleOfIncomeTaxRateReconciliationDetails" roleURI="http://www.helixesg.com/role/IncomeTaxesScheduleOfIncomeTaxRateReconciliationDetails">
        <link:definition>2409406 - Disclosure - Income Taxes - Schedule of Income Tax Rate Reconciliation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesTables" roleURI="http://www.helixesg.com/role/IncomeTaxesTables">
        <link:definition>2309301 - Disclosure - Income Taxes (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebt" roleURI="http://www.helixesg.com/role/LongTermDebt">
        <link:definition>2108100 - Disclosure - Long-Term Debt</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtConvertibleSeniorNotesDues2032Details" roleURI="http://www.helixesg.com/role/LongTermDebtConvertibleSeniorNotesDues2032Details">
        <link:definition>2408407 - Disclosure - Long-Term Debt - Convertible Senior Notes Dues 2032 (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtCreditAgreementDetails" roleURI="http://www.helixesg.com/role/LongTermDebtCreditAgreementDetails">
        <link:definition>2408403 - Disclosure - Long-Term Debt - Credit Agreement (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtInterestExpenseAndCapitalizedInterestDetails" roleURI="http://www.helixesg.com/role/LongTermDebtInterestExpenseAndCapitalizedInterestDetails">
        <link:definition>2408413 - Disclosure - Long-Term Debt - Interest Expense and Capitalized Interest (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtMaradDebtDetails" roleURI="http://www.helixesg.com/role/LongTermDebtMaradDebtDetails">
        <link:definition>2408408 - Disclosure - Long-Term Debt - MARAD Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtMaturitiesOfLongTermDebtDetails" roleURI="http://www.helixesg.com/role/LongTermDebtMaturitiesOfLongTermDebtDetails">
        <link:definition>2408412 - Disclosure - Long-Term Debt - Maturities of Long-Term Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtMaturitiesOfLongTermDebtDetailsCalc2" roleURI="http://www.helixesg.com/role/LongTermDebtMaturitiesOfLongTermDebtDetailsCalc2">
        <link:definition>2408412 - Disclosure - Long-Term Debt - Maturities of Long-Term Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtNordeaCreditAgreementDetails" roleURI="http://www.helixesg.com/role/LongTermDebtNordeaCreditAgreementDetails">
        <link:definition>2408409 - Disclosure - Long-Term Debt - Nordea Credit Agreement (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtOtherDetails" roleURI="http://www.helixesg.com/role/LongTermDebtOtherDetails">
        <link:definition>2408410 - Disclosure - Long-Term Debt - Other (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtScheduleOfConsolidatedInterestCoverageRatioDetails" roleURI="http://www.helixesg.com/role/LongTermDebtScheduleOfConsolidatedInterestCoverageRatioDetails">
        <link:definition>2408405 - Disclosure - Long-Term Debt - Schedule of Consolidated Interest Coverage Ratio (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtScheduleOfConsolidatedLeverageRatioCashBalancesDetails" roleURI="http://www.helixesg.com/role/LongTermDebtScheduleOfConsolidatedLeverageRatioCashBalancesDetails">
        <link:definition>2408406 - Disclosure - Long-Term Debt - Schedule of Consolidated Leverage Ratio Cash Balances (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtScheduleOfConsolidatedLeverageRatioDetails" roleURI="http://www.helixesg.com/role/LongTermDebtScheduleOfConsolidatedLeverageRatioDetails">
        <link:definition>2408404 - Disclosure - Long-Term Debt - Schedule of Consolidated Leverage Ratio (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtScheduleOfDeferredFinancingCostsDetails" roleURI="http://www.helixesg.com/role/LongTermDebtScheduleOfDeferredFinancingCostsDetails">
        <link:definition>2408411 - Disclosure - Long-Term Debt - Schedule of Deferred Financing Costs (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtScheduleOfLongTermDebtDetails" roleURI="http://www.helixesg.com/role/LongTermDebtScheduleOfLongTermDebtDetails">
        <link:definition>2408402 - Disclosure - Long-Term Debt - Schedule of Long-Term Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LongTermDebtTables" roleURI="http://www.helixesg.com/role/LongTermDebtTables">
        <link:definition>2308301 - Disclosure - Long-Term Debt (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="Organization" roleURI="http://www.helixesg.com/role/Organization">
        <link:definition>2101100 - Disclosure - Organization</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OrganizationDetails" roleURI="http://www.helixesg.com/role/OrganizationDetails">
        <link:definition>2401401 - Disclosure - Organization (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyAndEquipment" roleURI="http://www.helixesg.com/role/PropertyAndEquipment">
        <link:definition>2104100 - Disclosure - Property and Equipment</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyAndEquipmentGrossComponentsOfPropertyAndEquipmentDetails" roleURI="http://www.helixesg.com/role/PropertyAndEquipmentGrossComponentsOfPropertyAndEquipmentDetails">
        <link:definition>2404402 - Disclosure - Property and Equipment - Gross Components of Property and Equipment (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyAndEquipmentNarrativeDetails" roleURI="http://www.helixesg.com/role/PropertyAndEquipmentNarrativeDetails">
        <link:definition>2404403 - Disclosure - Property and Equipment - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyAndEquipmentTables" roleURI="http://www.helixesg.com/role/PropertyAndEquipmentTables">
        <link:definition>2304301 - Disclosure - Property and Equipment (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="QuarterlyFinancialInformationUnaudited" roleURI="http://www.helixesg.com/role/QuarterlyFinancialInformationUnaudited">
        <link:definition>2123100 - Disclosure - Quarterly Financial Information (Unaudited)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="QuarterlyFinancialInformationUnauditedDetails" roleURI="http://www.helixesg.com/role/QuarterlyFinancialInformationUnauditedDetails">
        <link:definition>2423402 - Disclosure - Quarterly Financial Information (Unaudited) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="QuarterlyFinancialInformationUnauditedTables" roleURI="http://www.helixesg.com/role/QuarterlyFinancialInformationUnauditedTables">
        <link:definition>2323301 - Disclosure - Quarterly Financial Information (Unaudited) (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ShareholdersEquity" roleURI="http://www.helixesg.com/role/ShareholdersEquity">
        <link:definition>2110100 - Disclosure - Shareholders' Equity</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ShareholdersEquityComponentsOfAccumulatedOciDetails" roleURI="http://www.helixesg.com/role/ShareholdersEquityComponentsOfAccumulatedOciDetails">
        <link:definition>2410403 - Disclosure - Shareholders' Equity - Components of Accumulated OCI (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ShareholdersEquityNarrativeDetails" roleURI="http://www.helixesg.com/role/ShareholdersEquityNarrativeDetails">
        <link:definition>2410402 - Disclosure - Shareholders' Equity - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ShareholdersEquityTables" roleURI="http://www.helixesg.com/role/ShareholdersEquityTables">
        <link:definition>2310301 - Disclosure - Shareholders' Equity (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementOfCashFlowInformation" roleURI="http://www.helixesg.com/role/StatementOfCashFlowInformation">
        <link:definition>2119100 - Disclosure - Statement of Cash Flow Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementOfCashFlowInformationNarrativeDetails" roleURI="http://www.helixesg.com/role/StatementOfCashFlowInformationNarrativeDetails">
        <link:definition>2419403 - Disclosure - Statement of Cash Flow Information - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementOfCashFlowInformationSupplementalCashFlowInformationDetails" roleURI="http://www.helixesg.com/role/StatementOfCashFlowInformationSupplementalCashFlowInformationDetails">
        <link:definition>2419402 - Disclosure - Statement of Cash Flow Information - Supplemental Cash Flow Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementOfCashFlowInformationTables" roleURI="http://www.helixesg.com/role/StatementOfCashFlowInformationTables">
        <link:definition>2319301 - Disclosure - Statement Of Cash Flow Information (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBuybackProgram" roleURI="http://www.helixesg.com/role/StockBuybackProgram">
        <link:definition>2111100 - Disclosure - Stock Buyback Program</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBuybackProgramDetails" roleURI="http://www.helixesg.com/role/StockBuybackProgramDetails">
        <link:definition>2411401 - Disclosure - Stock Buyback Program (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPolicies" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPolicies">
        <link:definition>2102100 - Disclosure - Summary of Significant Accounting Policies</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesAssetRetirementObligationsDetails" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPoliciesAssetRetirementObligationsDetails">
        <link:definition>2402408 - Disclosure - Summary of Significant Accounting Policies - Asset Retirement Obligations (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesForeignCurrencyDetails" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPoliciesForeignCurrencyDetails">
        <link:definition>2402406 - Disclosure - Summary of Significant Accounting Policies - Foreign Currency (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesGoodwillDetails" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPoliciesGoodwillDetails">
        <link:definition>2402404 - Disclosure - Summary of Significant Accounting Policies - Goodwill (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesMajorCustomersAndConcentrationOfCreditRiskDetails" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPoliciesMajorCustomersAndConcentrationOfCreditRiskDetails">
        <link:definition>2402407 - Disclosure - Summary of Significant Accounting Policies - Major Customers and Concentration of Credit Risk (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesPolicy" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPoliciesPolicy">
        <link:definition>2202201 - Disclosure - Summary of Significant Accounting Policies (Policy)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesPrinciplesOfConsolidationDetails" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPoliciesPrinciplesOfConsolidationDetails">
        <link:definition>2402402 - Disclosure - Summary of Significant Accounting Policies - Principles of Consolidation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesPropertyAndEquipmentDetails" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPoliciesPropertyAndEquipmentDetails">
        <link:definition>2402403 - Disclosure - Summary of Significant Accounting Policies - Property and Equipment (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SummaryOfSignificantAccountingPoliciesRecertificationCostsAndDeferredDryDockChargesDetails" roleURI="http://www.helixesg.com/role/SummaryOfSignificantAccountingPoliciesRecertificationCostsAndDeferredDryDockChargesDetails">
        <link:definition>2402405 - Disclosure - Summary of Significant Accounting Policies - Recertification Costs and Deferred Dry Dock Charges (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xsd:appinfo>
  </xsd:annotation>
  <xsd:element id="hlx_AccumulatedAmortizationDeferredDryDock" name="AccumulatedAmortizationDeferredDryDock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="hlx_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationInExcessOfModifiedLiabilityAwardsFairValue" name="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationInExcessOfModifiedLiabilityAwardsFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hlx_AnadarkoMember" name="AnadarkoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_AssetRetirementObligationNetOfWorkingCapital" name="AssetRetirementObligationNetOfWorkingCapital" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="hlx_CaesarMember" name="CaesarMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_CapitalizedInterest" name="CapitalizedInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="hlx_CapitalizedVesselProjectCostsMember" name="CapitalizedVesselProjectCostsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ConsolidatedInterestCoverageRatio" name="ConsolidatedInterestCoverageRatio" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="hlx_ConsolidatedLeverageRatioGreaterThanOrEqualTo3.50ButLessThan4.00Member" name="ConsolidatedLeverageRatioGreaterThanOrEqualTo3.50ButLessThan4.00Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_ConsolidatedLeverageRatioGreaterThanOrEqualTo4.00ButLessThan4.50Member" name="ConsolidatedLeverageRatioGreaterThanOrEqualTo4.00ButLessThan4.50Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_ConsolidatedLeverageRatioGreaterThanOrEqualTo4.50Member" name="ConsolidatedLeverageRatioGreaterThanOrEqualTo4.50Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_ConsolidatedLeverageRatioLessThan3.50Member" name="ConsolidatedLeverageRatioLessThan3.50Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_ConsolidatedLeverageRatioPeriodAxis" name="ConsolidatedLeverageRatioPeriodAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_ConsolidatedLeverageRatioPeriodDomain" name="ConsolidatedLeverageRatioPeriodDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ContractSigningMember" name="ContractSigningMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ConvertibleSeniorNotes2032Member" name="ConvertibleSeniorNotes2032Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_CorporateAndEliminationsMember" name="CorporateAndEliminationsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_CreditAgreementFebruary2016AmendmentMember" name="CreditAgreementFebruary2016AmendmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_CreditAgreementMay2015AmendmentMember" name="CreditAgreementMay2015AmendmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_DebtInstrumentCovenantMinimumCashAmount" name="DebtInstrumentCovenantMinimumCashAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="hlx_DebtInstrumentNoncurrent" name="DebtInstrumentNoncurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="hlx_DebtInstrumentPeriodicPaymentPrincipalPercentage" name="DebtInstrumentPeriodicPaymentPrincipalPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_DebtInstrumentRepurchaseAmountPercentage" name="DebtInstrumentRepurchaseAmountPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_DeepwaterGatewayLLCAndIndependenceHubLLCMember" name="DeepwaterGatewayLLCAndIndependenceHubLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_DeepwaterGatewayLLCMember" name="DeepwaterGatewayLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_DeferredCompensationArrangementWithIndividualAwardVestingPeriod" name="DeferredCompensationArrangementWithIndividualAwardVestingPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_DeferredCompensationArrangementWithIndividualSharesPurchasedThroughPayrollDeductionsPeriod" name="DeferredCompensationArrangementWithIndividualSharesPurchasedThroughPayrollDeductionsPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_DeferredDrydockExpensesNet" name="DeferredDrydockExpensesNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="hlx_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_DryDockAmortizationExpense" name="DryDockAmortizationExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlx_DryDockAmortizationPeriod" name="DryDockAmortizationPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_DryDockRecertificationProcessPeriod" name="DryDockRecertificationProcessPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_DueJune2016Member" name="DueJune2016Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ESPPMember" name="ESPPMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_EnergyResourceTechnologyGomIncMember" name="EnergyResourceTechnologyGomIncMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_EquityMethodInvestmentSummarizedFinancialInformationBalanceSheetAbstractAbstract" name="EquityMethodInvestmentSummarizedFinancialInformationBalanceSheetAbstractAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ExpressMember" name="ExpressMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_ExtendScheduledDeliveryMember" name="ExtendScheduledDeliveryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_FacilitiesAndOtherMember" name="FacilitiesAndOtherMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_FinancialRatioRangeAxis" name="FinancialRatioRangeAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_FinancialRatioRangeDomain" name="FinancialRatioRangeDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_ForeignExchangeContractsForGrandCanyonIIAndGrandCanyonIIIMember" name="ForeignExchangeContractsForGrandCanyonIIAndGrandCanyonIIIMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ForfeitureOnRestrictedStockPeriod" name="ForfeitureOnRestrictedStockPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ForfeituresOnRestrictedStockPercentage" name="ForfeituresOnRestrictedStockPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_FormerTermLoanMember" name="FormerTermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GainLossOnCommodityDerivativeContracts" name="GainLossOnCommodityDerivativeContracts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hlx_GrandCanyonIIIMember" name="GrandCanyonIIIMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GrandCanyonIIMember" name="GrandCanyonIIMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_GrandCanyonIIandIIIMember" name="GrandCanyonIIandIIIMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GrandCanyonMember" name="GrandCanyonMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GrantShareAmountBMember" name="GrantShareAmountBMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GrantShareAmountCMember" name="GrantShareAmountCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GrantShareAmountDMember" name="GrantShareAmountDMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GrantShareAmountEMember" name="GrantShareAmountEMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_GrantShareAmountFMember" name="GrantShareAmountFMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_GrantShareAmountGMember" name="GrantShareAmountGMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_GrantShareAmountHMember" name="GrantShareAmountHMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_GrantShareAmountIMember" name="GrantShareAmountIMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_GrantShareAmountJMember" name="GrantShareAmountJMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_GrantShareAmountKMember" name="GrantShareAmountKMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GrantShareAmountMember" name="GrantShareAmountMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_GulfOfMexicoOilAndGasPropertiesMember" name="GulfOfMexicoOilAndGasPropertiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_HPIMember" name="HPIMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Helix534Member" name="Helix534Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_IncentivePlan2005Member" name="IncentivePlan2005Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_IncrementalCostsAxis" name="IncrementalCostsAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_IncrementalCostsDomain" name="IncrementalCostsDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_IndependenceHubLlcMember" name="IndependenceHubLlcMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_InterestCoverageRatioPeriodAxis" name="InterestCoverageRatioPeriodAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_InterestCoverageRatioPeriodDomain" name="InterestCoverageRatioPeriodDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_IssuanceofCompletionCertificateMember" name="IssuanceofCompletionCertificateMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_LesseeLeasingArrangementsOperatingLeasesNumberOfRenewalOptions" name="LesseeLeasingArrangementsOperatingLeasesNumberOfRenewalOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_LineOfCreditFacilityMaximumAdditionalCommitments" name="LineOfCreditFacilityMaximumAdditionalCommitments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="hlx_LoanNotesMember" name="LoanNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_LongTermIncentiveCashPlansMember" name="LongTermIncentiveCashPlansMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_LongTermPurchaseCommitmentNumberOfPaymentInstallments" name="LongTermPurchaseCommitmentNumberOfPaymentInstallments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_LongTermPurchaseCommitmentPercentage" name="LongTermPurchaseCommitmentPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_LossFromEquityMethodInvestments" name="LossFromEquityMethodInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlx_MachineryEquipmentBuildingsAndLeaseholdImprovementsMember" name="MachineryEquipmentBuildingsAndLeaseholdImprovementsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_MaradDebtMember" name="MaradDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_MaximumSharesAsIncentiveOptionsMember" name="MaximumSharesAsIncentiveOptionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_MinimumPercentageOfAveragePriceDuringMeasurementPeriod" name="MinimumPercentageOfAveragePriceDuringMeasurementPeriod" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_ModifiedLiabilityPerformanceShareMember" name="ModifiedLiabilityPerformanceShareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_MonohullVesselsMember" name="MonohullVesselsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_NetIncomeLossAvailableToCommonStockholdersBasicContinuingOperations" name="NetIncomeLossAvailableToCommonStockholdersBasicContinuingOperations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hlx_NetIncomeLossAvailableToCommonStockholdersBasicDiscontinuedOperations" name="NetIncomeLossAvailableToCommonStockholdersBasicDiscontinuedOperations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hlx_NetInterestExpenseAndOther" name="NetInterestExpenseAndOther" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlx_NonHedgeLossOnCommodityDerivativeContractsMember" name="NonHedgeLossOnCommodityDerivativeContractsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_NordeaQ5000LoanMember" name="NordeaQ5000LoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_NorthSeaMember" name="NorthSeaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_NotesReceivableInterestStatedRatePercentage" name="NotesReceivableInterestStatedRatePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="hlx_NumberOfCharteredVessels" name="NumberOfCharteredVessels" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_NumberOfForeignSubsidiariesNotSubjectToCreditAgreementCovenants" name="NumberOfForeignSubsidiariesNotSubjectToCreditAgreementCovenants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_NumberOfStockPlans" name="NumberOfStockPlans" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_NumberOfVesselsUnderConstruction" name="NumberOfVesselsUnderConstruction" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_OilAndGasCommodityContractMember" name="OilAndGasCommodityContractMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_OperatingLeasesAnnualPaymentsDue" name="OperatingLeasesAnnualPaymentsDue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="hlx_OtherComprehensiveIncomeLossReclassificationAdjustmentOnDerivativesDedesignatedIncludedInNetIncomeBeforeTax" name="OtherComprehensiveIncomeLossReclassificationAdjustmentOnDerivativesDedesignatedIncludedInNetIncomeBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hlx_OtherGeographicRegionMember" name="OtherGeographicRegionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_PaymentTermsAxis" name="PaymentTermsAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_PaymentTermsDomain" name="PaymentTermsDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_PercentageOfShareOfNonVestedStockConsideredAsCallOption" name="PercentageOfShareOfNonVestedStockConsideredAsCallOption" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="hlx_PercentageOfShareOfNonVestedStockConsideredAsPutOption" name="PercentageOfShareOfNonVestedStockConsideredAsPutOption" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_PerformanceShareUnitMarketValue" name="PerformanceShareUnitMarketValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="hlx_PerformanceShareUnitsGranted" name="PerformanceShareUnitsGranted" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Period1Member" name="Period1Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Period2Member" name="Period2Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Period3Member" name="Period3Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Period4Member" name="Period4Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Period5Member" name="Period5Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Period6Member" name="Period6Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Period7Member" name="Period7Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_Period8Member" name="Period8Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ProceedsFromCharterAgreementNonrefundable" name="ProceedsFromCharterAgreementNonrefundable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlx_ProceedsFromEquityMethodInvestmentNetOfEarnings" name="ProceedsFromEquityMethodInvestmentNetOfEarnings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlx_ProductionFacilitiesMember" name="ProductionFacilitiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_Q7000Member" name="Q7000Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_QuarterlyFinancialInformationLineItems" name="QuarterlyFinancialInformationLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_QuarterlyFinancialInformationTable" name="QuarterlyFinancialInformationTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_RepaymentsOfLongTermSecuredDebt" name="RepaymentsOfLongTermSecuredDebt" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hlx_RestrictedStockUnitsAndRestrictedStockSharesMember" name="RestrictedStockUnitsAndRestrictedStockSharesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_RevolvingCreditFacilityMaturingJune2018Member" name="RevolvingCreditFacilityMaturingJune2018Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_RoboticsMember" name="RoboticsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_RovsAndVesselsMember" name="RovsAndVesselsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_RovsTrenchersAndRovdrillsMember" name="RovsTrenchersAndRovdrillsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_SalesPriceOfPropertyPlantAndEquipment" name="SalesPriceOfPropertyPlantAndEquipment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlx_ScheduleOfDistributionsFromEquityInvestmentsTableTextBlock" name="ScheduleOfDistributionsFromEquityInvestmentsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ScheduleOfNonDesignatedDerivativeInstrumentsEffectOnIncomeStatementTableTextBlock" name="ScheduleOfNonDesignatedDerivativeInstrumentsEffectOnIncomeStatementTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ScheduleOfRestrictedSharesGrantedToExecutiveOfficersManagementEmployeesAndNonEmployeeMembersTableTextBlock" name="ScheduleOfRestrictedSharesGrantedToExecutiveOfficersManagementEmployeesAndNonEmployeeMembersTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_SeniorUnsecuredNotesMember" name="SeniorUnsecuredNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantDate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantDate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:dateItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingDate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingDate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:dateItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingPercentage" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCostInExcessOfFairValue" name="SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCostInExcessOfFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlx_ShellMember" name="ShellMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_SpoolbaseFacilityMember" name="SpoolbaseFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_StockRepurchasedAndRetiredDuringPeriodAverageCostPerShare" name="StockRepurchasedAndRetiredDuringPeriodAverageCostPerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="hlx_SubseaConstructionMember" name="SubseaConstructionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_SummaryOfIntercompanySegmentRevenuesTableTextBlock" name="SummaryOfIntercompanySegmentRevenuesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlx_TalosMember" name="TalosMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_TermLoanMaturingJune2018Member" name="TermLoanMaturingJune2018Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_TermOfCharterAgreement" name="TermOfCharterAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_TopsideEquipmentMember" name="TopsideEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_TotalStockRepurchaseValue" name="TotalStockRepurchaseValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="hlx_UndiscountedNetIncomeFromDiscontinuedOperationsAllocableToParticipatingSecurities" name="UndiscountedNetIncomeFromDiscontinuedOperationsAllocableToParticipatingSecurities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlx_UndistributedEarningsReallocatedToParticipatingSecuritiesValue" name="UndistributedEarningsReallocatedToParticipatingSecuritiesValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hlx_VesselDeliveryMember" name="VesselDeliveryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_VesselsMember" name="VesselsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_WaterDepth" name="WaterDepth" nillable="true" substitutionGroup="xbrli:item" type="num:lengthItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_WeightedAverageNumberOfDilutedSharesIncludingAntiDilutiveSecurities" name="WeightedAverageNumberOfDilutedSharesIncludingAntiDilutiveSecurities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_WellInterventionMember" name="WellInterventionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlx_WriteOffOfDeferredDrydockExpenses" name="WriteOffOfDeferredDrydockExpenses" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
</xsd:schema>
