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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 PJsxuFXuyyUnuYqe66Znf5sZ+rhRThN32V86D6oHbS0YzhPKbF5mZQYEjUUvKskk
 CLWPc/N9WUwj4LZRVFIReA==

<SEC-DOCUMENT>0001209191-03-026585.txt : 20031023
<SEC-HEADER>0001209191-03-026585.hdr.sgml : 20031023
<ACCEPTANCE-DATETIME>20031023150640
ACCESSION NUMBER:		0001209191-03-026585
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031021
FILED AS OF DATE:		20031023

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GSE SYSTEMS INC
		CENTRAL INDEX KEY:			0000944480
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				521868008
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		9189 RED BRANCH ROAD
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21045
		BUSINESS PHONE:		4107723500

	MAIL ADDRESS:	
		STREET 1:		9189 RED BRANCH ROAD
		STREET 2:		9189 RED BRANCH ROAD
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21045

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MANTECH INTERNATIONAL CORP
		CENTRAL INDEX KEY:			0000892537
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MANAGEMENT SERVICES [8741]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14785
		FILM NUMBER:		03953971

	BUSINESS ADDRESS:	
		STREET 1:		12015 LEE JACKSON MEMORIAL HIGHWAY
		CITY:			FAIRFAX
		STATE:			VA
		ZIP:			22033-3300
		BUSINESS PHONE:		703-218-6000

	MAIL ADDRESS:	
		STREET 1:		12015 LEE JACKSON MEMORIAL HIGHWAY
		CITY:			FAIRFAX
		STATE:			VA
		ZIP:			22033-3300
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?><ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType><periodOfReport>2003-10-21</periodOfReport><notSubjectToSection16>1</notSubjectToSection16>
    <issuer>
        <issuerCik>0000944480</issuerCik>
        <issuerName>GSE SYSTEMS INC</issuerName>
        <issuerTradingSymbol>GVP</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000892537</rptOwnerCik>
            <rptOwnerName>MANTECH INTERNATIONAL CORP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>12015 LEE JACKSON MEMORIAL HIGHWAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>FAIRFAX</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22033</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector><isOfficer>0</isOfficer><isTenPercentOwner>1</isTenPercentOwner><isOther>0</isOther></reportingOwnerRelationship></reportingOwner><nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-10-21</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>3426699</value></transactionShares><transactionPricePerShare><value>1.3427</value><footnoteId id="F1" /></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>0</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><direct
OrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><footnotes><footnote id="F1">The reported securities were sold together with a promissory note for an aggregate amount of consideration.  The per share price of the reported securities was determined by subtracting the outstanding principal amount of the promissory note from the aggregate consideration received by the Reporting Person and then dividing that amount by the number of shares sold.</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>MANTECH INTERNATIONAL CORPORATION
By: Ronald R. Spoehel
Executive Vice President &amp; Chief Financial Officer</signatureName><signatureDate>2003-10-23</signatureDate></ownerSignature></ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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