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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 Wt6MYhMv12APKmEqLtHBkKwMh8N0z2xY/GgR7CSFTtKfVqM5Z2fEXaU7CZGvy6AM
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<SEC-DOCUMENT>0001209191-11-014080.txt : 20110301
<SEC-HEADER>0001209191-11-014080.hdr.sgml : 20110301
<ACCEPTANCE-DATETIME>20110301210302
ACCESSION NUMBER:		0001209191-11-014080
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110301
FILED AS OF DATE:		20110301
DATE AS OF CHANGE:		20110301

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Gansler Jacques S
		CENTRAL INDEX KEY:			0001341205

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34551
		FILM NUMBER:		11654100

	MAIL ADDRESS:	
		STREET 1:		1308 BALLANTRAE FARM DRIVE
		CITY:			MCCLEAN
		STATE:			VA
		ZIP:			22101

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GLOBAL DEFENSE TECHNOLOGY & SYSTEMS, INC.
		CENTRAL INDEX KEY:			0001471038
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ENGINEERING SERVICES [8711]
		IRS NUMBER:				204477465
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1501 FARM CREDIT DRIVE
		STREET 2:		SUITE 2300
		CITY:			MCLEAN
		STATE:			VA
		ZIP:			22102-5011
		BUSINESS PHONE:		703-738-2840

	MAIL ADDRESS:	
		STREET 1:		1501 FARM CREDIT DRIVE
		STREET 2:		SUITE 2300
		CITY:			MCLEAN
		STATE:			VA
		ZIP:			22102-5011
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-03-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001471038</issuerCik>
        <issuerName>GLOBAL DEFENSE TECHNOLOGY &amp; SYSTEMS, INC.</issuerName>
        <issuerTradingSymbol>GTEC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001341205</rptOwnerCik>
            <rptOwnerName>Gansler Jacques S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1501 FARM CREDIT DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 2300</rptOwnerStreet2>
            <rptOwnerCity>MCLEAN</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22102-5011</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2011-03-01</value>
                <footnoteId id="F2"/>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6845</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">On January 5, 2011, in conjunction with the Company's annual equity grants to employees and directors, the Compensation Committee of the GTEC Board tentatively approved the issuance of (1) Company Options to certain executive officers for the purchase of an aggregate of 39,000 shares of Common Stock and (2) 97,000 restricted shares to certain non-management members of the GTEC Board, including the filing person, and the Company's Chief Executive Officer and Chief Financial Officer. Following the meeting, the Compensation Committee sought additional information, including the market for compensation of Chief Executive Officers and Chief Financial Officers of peer companies, final tables containing the related grant information, and input from other directors. Following receipt of this information, the Compensation Committee formally approved the grants on January 28, 2011.</footnote>
        <footnote id="F2">Pursuant to the terms of the Company's Equity Award Grant Policy, all annual equity grants to the Company's employees and directors are effective as of the third trading day following the date that the Company releases its annual financial results. As a result, the grant date for these grants was March 1, 2011.</footnote>
        <footnote id="F3">Represents restricted shares that vest in three equal, annual installments beginning on the first anniversary of the Transaction Date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Lisa Broome</signatureName>
        <signatureDate>2011-03-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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