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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT

                       PURSUANT TO SECTION 13 OR 15(d) OF
                       THE SECURITIES EXCHANGE ACT OF 1934

       Date of Report (Date of earliest event reported): October 26, 2005

                             NETSCOUT SYSTEMS, INC.
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             (Exact Name of Registrant as Specified in its Charter)

                                    Delaware
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                 (State or Other Jurisdiction of Incorporation)

              0000-26251                                   04-2837575
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       (Commission File Number)                (IRS Employer Identification No.)

 310 Littleton Road, Westford, Massachusetts                   01886
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   (Address of Principal Executive Offices)                  (Zip Code)

                                 (978) 614-4000
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              (Registrant's Telephone Number, Including Area Code)

                                 Not Applicable
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          (Former Name or Former Address, If Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

[ ]  Written communications pursuant to Rule 425 under the Securities
     Act (17 CFR 230.425)

[ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange
     Act (17 CFR 240.14a-12)

[ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[ ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the
     Exchange Act (17 CFR 240.13e-4(c))

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ITEM 2.02. RESULTS OF OPERATIONS AND FINANCIAL CONDITION.

        The following information and the Exhibit attached hereto shall not be
deemed "filed" for purposes of Section 18 of the Securities Exchange Act of
1934, as amended (the "Exchange Act") or otherwise subject to the liabilities of
that section, nor shall it be deemed incorporated by reference in any filing
under the Securities Act of 1933, as amended, or the Exchange Act, except as
expressly set forth by specific reference in such filing.

        On October 26, 2005, NetScout Systems, Inc. (the "Company") issued a
press release regarding its financial results for the quarter ended September
30, 2005, its expectations of future performance and its intention to hold a
conference call regarding these topics. The Company's press release is furnished
as Exhibit 99.1 to this report and is incorporated herein by reference.

ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS.

(c)  Exhibits.

       The Company hereby furnishes the following exhibit:

       99.1     Press release dated October 26, 2005.



                                   SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                             NETSCOUT SYSTEMS, INC.

                                             By:
                                                  ------------------------------
                                                  David P. Sommers
                                                  Chief Financial Officer and
                                                  Senior Vice President,
                                                  General Operations

Date: October 26, 2005



                                  EXHIBIT INDEX

Exhibit  Number     Description
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99.1                Press release dated October 26, 2005.