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  <xsd:element id="ldos_LossContingencyPercentageofDamagesCoveredBetweenThirtyEightMillionandSixtyFourMillionSettlementAmount" name="LossContingencyPercentageofDamagesCoveredBetweenThirtyEightMillionandSixtyFourMillionSettlementAmount" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_LossContingencyPercentageofDamagesCoveredExcessofSixtyFourMillionSettlementAmount" name="LossContingencyPercentageofDamagesCoveredExcessofSixtyFourMillionSettlementAmount" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_MSAVentureMember" name="MSAVentureMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_MarylandProcurementOfficeMember" name="MarylandProcurementOfficeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_MaximumPercentageThatWillUltimatelyVestForSharesProvidedUnderLongTermPerformanceBasedIncentiveEquityAwardsBasedOnTargetAmountStatedInAgreement" name="MaximumPercentageThatWillUltimatelyVestForSharesProvidedUnderLongTermPerformanceBasedIncentiveEquityAwardsBasedOnTargetAmountStatedInAgreement" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_May2013SalesLeaseBackAgreementMember" name="May2013SalesLeaseBackAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_MilestoneTwoMember" name="MilestoneTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_NationalSecuritySolutionsMember" name="NationalSecuritySolutionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_NoteReceivableInterestRateStatedPercentage" name="NoteReceivableInterestRateStatedPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_NoteReceivableInterestRateStatedPercentageIfMaturityisExtendedBeyondJulyTwentyFourTwentyNineteen" name="NoteReceivableInterestRateStatedPercentageIfMaturityisExtendedBeyondJulyTwentyFourTwentyNineteen" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_NoteReceivableInterestRateStatedPercentageIfMaturityisExtendedBeyondJulyTwentyFourTwentySeventeen" name="NoteReceivableInterestRateStatedPercentageIfMaturityisExtendedBeyondJulyTwentyFourTwentySeventeen" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_NoteReceivableOptiontoExtendforOneYearPeriodNumber" name="NoteReceivableOptiontoExtendforOneYearPeriodNumber" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_NotesPayableandLongTermDebtNetofCurrentPortionMember" name="NotesPayableandLongTermDebtNetofCurrentPortionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_NotesWhichMatureOnDecemberTwoThousandFortyMember" name="NotesWhichMatureOnDecemberTwoThousandFortyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_NotesWhichMatureOnDecemberTwoThousandTwentyMember" name="NotesWhichMatureOnDecemberTwoThousandTwentyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_NotesWhichMatureOnJulyTwoThousandThirtyThreeMember" name="NotesWhichMatureOnJulyTwoThousandThirtyThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_NotesWhichMatureOnJulyTwoThousandThirtyTwoMember" name="NotesWhichMatureOnJulyTwoThousandThirtyTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_NumberOfLawsuits" name="NumberOfLawsuits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_NumberOfPatentsInfringed" name="NumberOfPatentsInfringed" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_NumberofFormerChiefExecutiveOfficers" name="NumberofFormerChiefExecutiveOfficers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_NumberofProjects" name="NumberofProjects" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_OldRevolvingCreditFacilityMember" name="OldRevolvingCreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_OneBusinessMember" name="OneBusinessMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_OneCustomerMember" name="OneCustomerMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_OperatingCyclePolicyTextBlock" name="OperatingCyclePolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_OperatingIncomeLossMargin" name="OperatingIncomeLossMargin" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_OperatingLeaseObligationNoncurrent" name="OperatingLeaseObligationNoncurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_OtherCommitmentsAndContingenciesLineItems" name="OtherCommitmentsAndContingenciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_OtherCommitmentsAndContingenciesTable" name="OtherCommitmentsAndContingenciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_OtherDisposalsMember" name="OtherDisposalsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_OtherIncomeExpenseNet" name="OtherIncomeExpenseNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_OtherIncomeNetMember" name="OtherIncomeNetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_OtherIntegrationCosts" name="OtherIntegrationCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ldos_OtherLiabilitiesNoncurrentOther" name="OtherLiabilitiesNoncurrentOther" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_OtherNoncurrentLiabilitiesAbstract" name="OtherNoncurrentLiabilitiesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_OutsideDirectorsMember" name="OutsideDirectorsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_ParticipantsMaximumPercentageOfEligibleSalaryDefer" name="ParticipantsMaximumPercentageOfEligibleSalaryDefer" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_PaymentsforLeaseTerminationFees" name="PaymentsforLeaseTerminationFees" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ldos_PaymentstoParentSpecialPayment" name="PaymentstoParentSpecialPayment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_PensionAndOtherPostretirementBenefitsDisclosureLineItems" name="PensionAndOtherPostretirementBenefitsDisclosureLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_PensionAndOtherPostretirementBenefitsDisclosureTable" name="PensionAndOtherPostretirementBenefitsDisclosureTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_PercentageOfMarketPriceDuringNonCompensatoryPeriod" name="PercentageOfMarketPriceDuringNonCompensatoryPeriod" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_PercentageOfMarketPriceofSharesForStockPurchaseProgram" name="PercentageOfMarketPriceofSharesForStockPurchaseProgram" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_PercentageOfStockAwardsVestOrExercisable" name="PercentageOfStockAwardsVestOrExercisable" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_PercentageOfStockAwardsVestOrExercisableAfterFourYears" name="PercentageOfStockAwardsVestOrExercisableAfterFourYears" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_PercentageOfStockAwardsVestOrExercisableAfterThreeYears" name="PercentageOfStockAwardsVestOrExercisableAfterThreeYears" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_PercentageOfStockCompensationPlansAwardsVestAfterVestingPeriod" name="PercentageOfStockCompensationPlansAwardsVestAfterVestingPeriod" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_PercentageofOwnership" name="PercentageofOwnership" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_PlainfieldRenewalEnergyHoldingsLLCMember" name="PlainfieldRenewalEnergyHoldingsLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_PrepaidBeforeDecemberSeventeenTwentyEighteenMember" name="PrepaidBeforeDecemberSeventeenTwentyEighteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_PrepaidContractCosts" name="PrepaidContractCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_PrepaidPriortoMaturityMember" name="PrepaidPriortoMaturityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_ProceedsfromGovernmentGrant" name="ProceedsfromGovernmentGrant" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ldos_ProjectAssetsPolicyPolicyTextBlock" name="ProjectAssetsPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_PurchaserofthePropertyMember" name="PurchaserofthePropertyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_QuarterlyFinancialInformationLineItems" name="QuarterlyFinancialInformationLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_QuarterlyFinancialInformationTable" name="QuarterlyFinancialInformationTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_RatioOfConsolidatedFundedDebtToEarningsBeforeInterestTaxesDepreciationAndAmortizationNumeratorAfterFebruarySixteenTwentyNineteen" name="RatioOfConsolidatedFundedDebtToEarningsBeforeInterestTaxesDepreciationAndAmortizationNumeratorAfterFebruarySixteenTwentyNineteen" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_RatioOfConsolidatedFundedDebtToEarningsBeforeInterestTaxesDepreciationAndAmortizationNumeratorMaximumFromFebruarySixteenTwentyEighteentoFebruarySixteenTwentyNineteen" name="RatioOfConsolidatedFundedDebtToEarningsBeforeInterestTaxesDepreciationAndAmortizationNumeratorMaximumFromFebruarySixteenTwentyEighteentoFebruarySixteenTwentyNineteen" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_RatioOfConsolidatedFundedDebtToEarningsBeforeInterestTaxesDepreciationAndAmortizationNumeratorMaximumUntilFebruarySixteenTwentyEighteen" name="RatioOfConsolidatedFundedDebtToEarningsBeforeInterestTaxesDepreciationAndAmortizationNumeratorMaximumUntilFebruarySixteenTwentyEighteen" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_RemainingTermofCapitalLease" name="RemainingTermofCapitalLease" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_RestrictedCashPolicyTextBlock" name="RestrictedCashPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_RestructuringChargesIncludingSeparationCosts" name="RestructuringChargesIncludingSeparationCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ldos_RestructuringLiabilityPeriodtoSettle" name="RestructuringLiabilityPeriodtoSettle" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_RevealImagingTechnologiesInc.Member" name="RevealImagingTechnologiesInc.Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_SAICMember" name="SAICMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_SalariesBonusesAndAmountsWithheldFromEmployeesCompensation" name="SalariesBonusesAndAmountsWithheldFromEmployeesCompensation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="ldos_ScheduleOfCertainFinancialStatementCaptionsTextBlock" name="ScheduleOfCertainFinancialStatementCaptionsTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_ScheduleOfClassifiedDeferredTaxAssetsAndLiabilitiesTableTextBlock" name="ScheduleOfClassifiedDeferredTaxAssetsAndLiabilitiesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_ScheduleOfShareBasedCompensationAndRelatedTaxBenefitsRecognizedTableTextBlock" name="ScheduleOfShareBasedCompensationAndRelatedTaxBenefitsRecognizedTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_SecondAcceleratedShareRepurchaseFinalDeliveryMember" name="SecondAcceleratedShareRepurchaseFinalDeliveryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_SecondAcceleratedShareRepurchaseInitialDeliveryMember" name="SecondAcceleratedShareRepurchaseInitialDeliveryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_SecondAcceleratedShareRepurchaseMember" name="SecondAcceleratedShareRepurchaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_SecuritiesClassActionsMember" name="SecuritiesClassActionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_SeparationofNewSAICandRealEstateOptimizationInitiativesMember" name="SeparationofNewSAICandRealEstateOptimizationInitiativesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdjustmentForSpecialCashDividend" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdjustmentForSpecialCashDividend" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm2" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm2" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodWeightedAverageGrantDateStockPrice" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodWeightedAverageGrantDateStockPrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_SharebasedCompensationDecreaseinStrikePricebyFactor" name="SharebasedCompensationDecreaseinStrikePricebyFactor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_SharebasedCompensationIncreaseinNumberofSharesIssuableUponExerciseofEachOption" name="SharebasedCompensationIncreaseinNumberofSharesIssuableUponExerciseofEachOption" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_SharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodExcludingDividendsEquivalentsWeightedAverageGrantDateFairValue" name="SharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodExcludingDividendsEquivalentsWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_SignificantAccountingPoliciesTable" name="SignificantAccountingPoliciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_SpecialDividendDeclared" name="SpecialDividendDeclared" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ldos_SpecialDividendPaid" name="SpecialDividendPaid" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ldos_SpecialDividendPerShareDeclared" name="SpecialDividendPerShareDeclared" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_StockConversionUponDivestiture" name="StockConversionUponDivestiture" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="ldos_StockIssuedDuringPeriodNewIssuesNetofCancellationsShares" name="StockIssuedDuringPeriodNewIssuesNetofCancellationsShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_StockIssuedDuringPeriodValueNewIssuesNetofCancellations" name="StockIssuedDuringPeriodValueNewIssuesNetofCancellations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ldos_StrategicAcquisitionandIntegrationCosts" name="StrategicAcquisitionandIntegrationCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ldos_SuretyBondsAmountOutstanding" name="SuretyBondsAmountOutstanding" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="ldos_TaxIndemnityLiability" name="TaxIndemnityLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_TermLoanADollarSixHundredandNinetyMillionDueAugustTwentyTwentyOneMember" name="TermLoanADollarSixHundredandNinetyMillionDueAugustTwentyTwentyOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_TermLoanADollarThreeHundredandTenMillionDueAugustTwentyTwentyOneMember" name="TermLoanADollarThreeHundredandTenMillionDueAugustTwentyTwentyOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_TermLoanADueAugustTwentyNineteenMember" name="TermLoanADueAugustTwentyNineteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_TermLoanAMember" name="TermLoanAMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_TermLoanBDueAugustTwentyTwentyThreeMember" name="TermLoanBDueAugustTwentyTwentyThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_TermLoanBMember" name="TermLoanBMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_ThirdAcceleratedShareRepurchaseMember" name="ThirdAcceleratedShareRepurchaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_ThirdPartyCreditEnhancementAmount" name="ThirdPartyCreditEnhancementAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_ThirtydayLIBORMember" name="ThirtydayLIBORMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_TransitionCostsPolicyPolicyTextBlock" name="TransitionCostsPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_TransitionCostsandProjectAssets" name="TransitionCostsandProjectAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ldos_TwoThousandSixEquityIncentivePlanMember" name="TwoThousandSixEquityIncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_USArmyMember" name="USArmyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_USDoDMember" name="USDoDMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_USGovernmentMember" name="USGovernmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ldos_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositionsAndSettlementsWithTaxAuthorities" name="UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositionsAndSettlementsWithTaxAuthorities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_ValueAddedTaxesMember" name="ValueAddedTaxesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_VestingStockAwardsMember" name="VestingStockAwardsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_VirnetXIncMember" name="VirnetXIncMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ldos_VitalizeandmaxITMember" name="VitalizeandmaxITMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
