-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
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 U5Wc/ECe/O+Z1O6ptceeBg==

<SEC-DOCUMENT>0001181431-05-052193.txt : 20050916
<SEC-HEADER>0001181431-05-052193.hdr.sgml : 20050916
<ACCEPTANCE-DATETIME>20050916174533
ACCESSION NUMBER:		0001181431-05-052193
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050914
FILED AS OF DATE:		20050916
DATE AS OF CHANGE:		20050916

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SCHICIANO KENNETH T
		CENTRAL INDEX KEY:			0001267209

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26251
		FILM NUMBER:		051089835

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		6175746781

	MAIL ADDRESS:	
		STREET 1:		125 HIGH ST STE 2500
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

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:		4 TECHNOLOGY PARK DR
		CITY:			WESTFORD
		STATE:			MA
		ZIP:			01886
		BUSINESS PHONE:		9786144000

	MAIL ADDRESS:	
		STREET 1:		4 TECHNOLOGY PARK DRIVE
		CITY:			WESTFORD
		STATE:			MA
		ZIP:			01886
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd92291.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-09-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001267209</rptOwnerCik>
            <rptOwnerName>SCHICIANO KENNETH T</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>125 HIGH STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 2500</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>93259</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote 1</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>26837</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote 3</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5613</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Directors Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F6"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-09-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5535</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F9"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F8"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5535</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5535</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeHolding>
            <securityTitle>
                <value>Directors Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>5.41</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2004-10-14</value>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-10-14</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Directors Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>21.25</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2003-09-22</value>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <value>2012-09-22</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>30000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Directors Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>5.67</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2005-09-15</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-09-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person may be deemed to have an indirect pecuniary interest as a member of TA Investors LLC in 93,259 shares of Common Stock.  The reporting person disclaims beneficial ownership of all such securities, except to the extent of 14,311 shares of Common Stock as to which he holds a pecuniary interest.</footnote>
        <footnote id="F2">10,000 stock options are exercisable on 9/15/05, provided that during such year, the reporting person attends at least 75% of the meetings of any committee of the Board of which the reporting person is a member. In the event the attendance requirements are not met, the options will not become exercisable until 9/15/07.</footnote>
        <footnote id="F3">The reporting person may be deemed to have an indirect pecuniary interest as a partner of High Street Partners L.P. in 26,837 shares of Common Stock. The reporting person disclaims beneficial ownership of all such securities, except to the extent of 3,354 shares of Common Stock as to which he holds a pecuniary interest.</footnote>
        <footnote id="F4">10,000 stock options are exercisable on 10/14/04, provided that during such year, the reporting person attends at least 75% of the meetings of any committee of the Board of which the reporting person is a member. In the event the attendance requirements are not met, the options will not become exercisable until 10/14/06.</footnote>
        <footnote id="F5">Options fully exercisable on 9/22/03.</footnote>
        <footnote id="F6">Price is N/A.</footnote>
        <footnote id="F7">5,535 restricted stock units vest on 9/14/06, provided that during the period from 9/14/05 through the date of the Annual Meeting, the reporting person attends at least 75% of the meetings of the Board and at least 75% of the meetings of any committee of the board which the reporting person is a member. In the event the attendance requirements are not met, the restricted stock units will not become vested until 9/14/08.</footnote>
        <footnote id="F8">Date is N/A.</footnote>
        <footnote id="F9">Price is N/A.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Kenneth T. Schiciano</signatureName>
        <signatureDate>2005-09-16</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>By: Thomas P. Alber, Attorney-in-Fact</signatureName>
        <signatureDate>2005-09-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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