<SEC-DOCUMENT>0000899243-15-001241.txt : 20150715
<SEC-HEADER>0000899243-15-001241.hdr.sgml : 20150715
<ACCEPTANCE-DATETIME>20150715161701
ACCESSION NUMBER:		0000899243-15-001241
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20150714
FILED AS OF DATE:		20150715
DATE AS OF CHANGE:		20150715

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NETSCOUT SYSTEMS INC
		CENTRAL INDEX KEY:			0001078075
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER INTEGRATED SYSTEMS DESIGN [7373]
		IRS NUMBER:				042837575
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		310 LITTLETON ROAD
		CITY:			WESTFORD
		STATE:			MA
		ZIP:			01886
		BUSINESS PHONE:		978-614-4000

	MAIL ADDRESS:	
		STREET 1:		310 LITTLETON ROAD
		CITY:			WESTFORD
		STATE:			MA
		ZIP:			01886

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LICO JAMES A
		CENTRAL INDEX KEY:			0001210231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26251
		FILM NUMBER:		15989477
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2015-07-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001078075</issuerCik>
        <issuerName>NETSCOUT SYSTEMS INC</issuerName>
        <issuerTradingSymbol>NTCT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001210231</rptOwnerCik>
            <rptOwnerName>LICO JAMES A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NETSCOUT SYSTEMS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>310 LITTLETON ROAD</rptOwnerStreet2>
            <rptOwnerCity>WESTFORD</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01886</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>
            </securityTitle>
            <transactionDate>
                <value>2015-07-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4994</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4994</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Unit</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2015-07-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>413</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>413</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>413</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person tendered 2,500 shares of common stock of Danaher Corporation (&quot;Danaher&quot;) in the exchange offer commenced by Danaher on May 14, 2015 (the &quot;Exchange Offer&quot;) in exchange for 2.4000 common units of Potomac Holding LLC (&quot;Newco&quot;) per share of Danaher common stock tendered, which is adjusted by a preliminary proration factor of 83.24%. In connection with the previously announced merger (the &quot;Merger&quot;) of a wholly-owned subsidiary of NetScout Systems, Inc. (&quot;NetScout&quot;) with Newco, each common unit of Newco received by the reporting person in the exchange offer converted automatically into one share of NetScout common stock. The number of shares of NetScout common stock set forth above to be acquired by the reporting person represents an estimate and is subject to change as a result of the final proration factor to be announced by Danaher. The reporting person undertakes to amend this report as necessary upon the determination of the final proration factor.</footnote>
        <footnote id="F2">Received in exchange for 4,994 common units of Newco, which Mr. Lico became entitled to following his tender of 2,500 shares of Danaher stock in the Exchange Offer.  As described in the note above, in the Merger, each outstanding common unit of Newco was converted into the right to receive one share of NetScout common stock (with cash being paid in lieu of fractional shares). On July 13, 2015, the last trading day prior to the closing date of the Merger, the closing price of NetScout common stock was $36.89 per share.  The closing price of Danaher common stock on July 13, 2015 was $88.00 per share.</footnote>
        <footnote id="F3">Price is N/A.</footnote>
        <footnote id="F4">All of the Restricted Stock Units vest on the date of the Company's Annual Meeting to occur in 2015, provided that during the period from the date of grant through the date of such Annual Meeting, the reporting person attends at least 75% of the meetings, collectively, of the Board and any committee of the Board of which the reporting person is a member.  In the event that the attendance requirements are not met, the Restricted Stock Units will not become vested until 7/14/2018.</footnote>
        <footnote id="F5">Date is N/A.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Greg Sloan, by Power of Attorney</signatureName>
        <signatureDate>2015-07-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
