<SEC-DOCUMENT>0001209191-15-047309.txt : 20150528
<SEC-HEADER>0001209191-15-047309.hdr.sgml : 20150528
<ACCEPTANCE-DATETIME>20150528105304
ACCESSION NUMBER:		0001209191-15-047309
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20150526
FILED AS OF DATE:		20150528
DATE AS OF CHANGE:		20150528

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MERCURY SYSTEMS INC
		CENTRAL INDEX KEY:			0001049521
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRONIC COMPONENTS & ACCESSORIES [3670]
		IRS NUMBER:				042741391
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		201 RIVERNECK ROAD
		CITY:			CHELMSFORD
		STATE:			MA
		ZIP:			01824
		BUSINESS PHONE:		9782561300

	MAIL ADDRESS:	
		STREET 1:		201 RIVERNECK ROAD
		CITY:			CHELMSFORD
		STATE:			MA
		ZIP:			01824

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MERCURY COMPUTER SYSTEMS INC
		DATE OF NAME CHANGE:	19971112

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			THIBAUD DIDIER M C
		CENTRAL INDEX KEY:			0001211771

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-23599
		FILM NUMBER:		15894312

	MAIL ADDRESS:	
		STREET 1:		199 RIVERNECK ROAD
		CITY:			CHEISFORD
		STATE:			MA
		ZIP:			01824
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
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        <issuerName>MERCURY SYSTEMS INC</issuerName>
        <issuerTradingSymbol>MRCY</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>THIBAUD DIDIER M C</rptOwnerName>
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            <rptOwnerStreet1>201 RIVERNECK ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHELMSFORD</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01824</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, MCE</officerTitle>
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    <derivativeTable>
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                <value>Non-Qualified Stock Option (Right to buy)</value>
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            <transactionDate>
                <value>2015-05-26</value>
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            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>12839</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2012-06-10</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-06-10</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12839</value>
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            <transactionDate>
                <value>2015-05-27</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
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                    <footnoteId id="F1"/>
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                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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            </exerciseDate>
            <expirationDate>
                <value>2015-06-10</value>
            </expirationDate>
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                <underlyingSecurityTitle>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The exercise of the stock option and sale of the underlying shares reported herein was pursuant to a 10b5-1 trading plan for a stock option expiring on June 10, 2015.  The Company's 2005 Stock Incentive Plan does not contain a net exercise feature for stock options and accordingly the option was exercised in full.</footnote>
        <footnote id="F2">Field N/A to this transaction but was completed to allow for electronic filing only.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Charles A. Speicher (Attorney-in-fact)</signatureName>
        <signatureDate>2015-05-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
