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                                                                    Exhibit 31.2



                                 CERTIFICATIONS

I, Charles D. Hamm, certify that:

1.   I have reviewed this quarterly report on Form 10-Q of ProCentury
     Corporation ("ProCentury");

2.   Based on my knowledge, this 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 this
     report;

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

4.   ProCentury'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 ProCentury and have:

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

          b)   evaluated the effectiveness of ProCentury's disclosure controls
               and procedures and presented in this report our conclusions about
               the effectiveness of the disclosure controls and procedures as at
               the end of the period concerned by this report based on such
               evaluation;

          c)   disclosed in this report any change in ProCentury's internal
               control over financial reporting that occurred during
               ProCentury's most recent fiscal quarter that has materially
               affected, or is reasonably likely to materially affect,
               ProCentury's internal control over financial reporting; and

5.   ProCentury's other certifying officers and I have disclosed, based on our
     most recent evaluation of internal control over financial reporting, to
     ProCentury's auditors and the audit committee of ProCentury's 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 ProCentury'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 ProCentury's
               internal control over financial reporting.

                June 4, 2004
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               Date

                /s/ Charles D. Hamm
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               Signature

               Chief Financial Officer and Treasurer
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               Title