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                                                                    EXHIBIT 31.1

                            CERTIFICATION PURSUANT TO
                  SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002


I, Michael H. Lee, certify that:

1.   I have reviewed the Annual Report of Tower Group, Inc. (the "Company")
     on Form 10-K for the period ending December 31, 2004 as filed with the
     Securities and Exchange Commission on the date hereof (the "Report");

2.   Based on my knowledge, the Report does not contain any untrue statement
     of a material fact or omit to state a material fact necessary to make
     the statements made, in light of the circumstances under which such
     statements were made, not misleading with respect to the period covered
     by the Report;

3.   Based on my knowledge, the financial statements, and other financial
     information included in the Report, fairly present in all material
     respects the financial condition, results of operations and cash flows
     of the Company as of, and for, the periods presented in the Report;

4.   The Company's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as
     defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the Company
     and have:

     (a) designed such disclosure controls and procedures, or caused such
     disclosure controls and procedures to be designed under our
     supervision, to ensure that material information relating to the
     Company, including its consolidated subsidiaries, is made known to us
     by others within those entities, particularly during the period in
     which the Report is being prepared;

     (b) evaluated the effectiveness of the Company's disclosure controls
     and procedures and presented in the Report our conclusions about the
     effectiveness of the disclosure controls and procedures, as of the end
     of the period covered by the Report based on such evaluation; and

      (c) disclosed in the Report that there were no changes in the
     Company's internal control over financial reporting that occurred
     during the Company's third quarter of 2004 that has materially
     affected, or is reasonably likely to materially affect, the Company's
     internal control over financial reporting; and

5.   The Company's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial
     reporting, to the Company's auditors and to the audit committee of the
     Board of Directors:

     a)   all significant deficiencies and material weaknesses in the
          design or operation of internal control over financial
          reporting which are reasonably likely to adversely affect the
          Company's ability to record, process, summarize and report
          financial information; and

     b)   any fraud, whether or not material, that involves management
          or other employees who have a significant role in the
          Company's internal control over financial reporting.


/s/ Michael H. Lee
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Michael H. Lee
Chief Executive Officer
March 21, 2005