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 Quarterly Report of Tower Group, Inc. (the "Company")
     on Form 10-Q for the period ending September 30, 2005 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 any changes in the Company's internal
               control over financial reporting that occurred during the
               Company's third quarter of 2005 that have materially affected, or
               are 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
November 9, 2005
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