-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 ON6qG7aMqTwoGQ4HyJgSYHDpiXnbsMJTB7SURzkQ6igiA3YiU3WOGLMmxATkS3+w
 evG7Fn4RqVAFXfrTZjShnQ==

<SEC-DOCUMENT>0001225201-05-000001.txt : 20050803
<SEC-HEADER>0001225201-05-000001.hdr.sgml : 20050803
<ACCEPTANCE-DATETIME>20050803194322
ACCESSION NUMBER:		0001225201-05-000001
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050729
FILED AS OF DATE:		20050803
DATE AS OF CHANGE:		20050803

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MCGUIGAN STUART M
		CENTRAL INDEX KEY:			0001335234

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26251
		FILM NUMBER:		05997323

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		603-245-3300

	MAIL ADDRESS:	
		STREET 1:		74 AGAMENTICUS AVENUE
		CITY:			CAPE NEDDICK
		STATE:			ME
		ZIP:			03902
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2005-07-29</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001335234</rptOwnerCik>
            <rptOwnerName>MCGUIGAN STUART M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>74 AGAMENTICUS AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CAPE NEDDICK</rptOwnerCity>
            <rptOwnerState>ME</rptOwnerState>
            <rptOwnerZipCode>03902</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>Stuart M. McGuigan</signatureName>
        <signatureDate>2005-08-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----