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

                                   FORM 10-K/A
                                (Amendment No. 1)

   (Mark One)      ANNUAL REPORT PRUSUANT TO SECTION 13 OR 15(d)
      [X]          OF THE SECURITIES EXCHANGE ACT OF 1934

                   For the fiscal year ended December 31, 2005
                                       Or

      [ ]          TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
                   OF THE SECURITIES ACT OF 1934

                        For the transition period from to

                        Commission File Number: 000-50990

                                Tower Group, Inc.
             (Exact name of registrant as specified in its charter)

                   Delaware                                  13-3894120
        (State or other jurisdiction of                   (I.R.S. Employer
         incorporation or organization)                  Identification No.)

            120 Broadway, 14th Floor
               New York, New York                              10271
    (Address of principal executive offices)                 (Zip Code)

                                 (212) 655-2000
              (Registrant's telephone number, including area code)

           Securities registered pursuant to Section 12(b) of the Act:
                                      None


           Securities registered pursuant to Section 12(g) of the Act:
                     Common Stock, $0.0l par value per share

     Indicate by check mark if the registrant is a well-known seasoned issuer,
as defined in Rule 405 of Securities Act.  Yes [ ]    No [X]


     Indicate by check mark if the registrant is not required to file reports
pursuant to Section 13 or Section 15(d) of the Act.  Yes [ ]    No [X]

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes [X]    No [ ]

     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of the registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K.    [X}

     Indicate by check mark whether the registrant is a large accelerated filer,
an accelerated filer, or a non-accelerated filer. See definition of "accelerated
filer and large accelerated filer: in Rule 12b-2 of the Exchange Act. (Check
one):
Large accelerated filer [ ]   Accelerated filer [X]   Non-accelerated filer [ ]

     Indicate by check mark whether the registrant is a shell company (as
defined in Rule 12b-2 of the Act).  Yes [ ]    No [X]

     The aggregate market value of the registrant's common stock held by
non-affiliates on June 30, 2005 (based on the closing price on the Nasdaq
National Market) on such date was approximately $264,037,653.

     As of March 10, 2006, the registrant had 19,855,841 shares of common stock
outstanding.

                      DOCUMENTS INCORPORATED BY REFERENCE:


<PAGE>

     Part III of this Form 10-K incorporates by reference certain information
from the registrant's definitive Proxy Statement with respect to the
registrant's 2006 Annual Meeting of Shareholders, to be filed not later than 120
days after the close of the registrant's fiscal year (the "Proxy Statement").

                                EXPLANATORY NOTE


     This Amendment No. 1 to the Annual Report on Form 10-K is being filed
solely to amend Exhibit 23.1 (Consent of Johnson Lambert & Co., Independent
Registered Public Accounting Firm) and to correct the identification of Tower
Group, Inc. as a well-known seasoned issuer on the cover page. Unaffected items
have not been repeated in this Amendment No. 1.

     Except as described above, no other changes have been made to the original
Form 10-K, and this Form 10-K/A does not amend, update or change the financial
statements or any other items or disclosures in the original Form 10-K. This
Form 10-K/A does not reflect events occurring after the filing of the Form 10-K
or modify or update those disclosures, including any exhibits to the Form 10-K
affected by subsequent events. Information not affected by the changes described
above is unchanged and reflects the disclosures made at the time of the original
filing of the Form 10-K on March 15, 2006. Accordingly, this Form 10-K/A should
be read in conjunction with our filings made with the Securities and Exchange
Commission subsequent to the filing of the original Form 10-K, including any
amendments to those filings.


Item 15.   Exhibits, Financial Statement Schedules

           (a) The following documents are filed as part of this report:

           1. Exhibits:

23.1 Amended Consent of Johnson Lambert & Co., Independent Registered Public
Accounting Firm


SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) 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.


                                       DATED: MAY 18, 2006

                                       TOWER GROUP, INC.

                                       BY:        /S/ MICHAEL H. LEE
                                          --------------------------------------
                                       NAME:   MICHAEL H. LEE
                                       TITLE:  CHAIRMAN OF THE BOARD, PRESIDENT
                                               AND CHIEF EXECUTIVE OFFICER