<PAGE>

Exhibit 31.2

                          WESTERN RESERVE BANCORP, INC.
                                   FORM 10-QSB
                        QUARTER ENDED SEPTEMBER 30, 2004

                                 CERTIFICATIONS

I, Cynthia A. Mahl, Senior Vice President and Chief Financial Officer of Western
Reserve Bancorp, Inc. (the "small business issuer"), certify that:

1.    I have reviewed this quarterly report on Form 10-QSB of Western Reserve
      Bancorp, Inc.;

2.    Based on my knowledge, this report does not contain any untrue statement
      of a material fact or omit to state a 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 report, fairly present in all material
      respects the financial condition, results of operations and cash flows of
      the small business issuer as of, and for, the periods presented in this
      report;

4.    The small business issuer's other certifying officers 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 small business issuer 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
            small business issuer, including its consolidated subsidiaries, is
            made known to us by others within those entities, particularly
            during the period in which this report is being prepared;

      (b)   Evaluated the effectiveness of the small business issuer's
            disclosure controls and procedures and presented in this report our
            conclusions about the effectiveness of the disclosure controls and
            procedures, as of the end of the period covered by this report based
            on such evaluation; and

      (c)   Disclosed in this report any change in the small business issuer's
            internal control over financial reporting that occurred during the
            small business issuer's most recent fiscal quarter (the small
            business issuer's fourth fiscal quarter in the case of an annual
            report) that has materially affected, or is reasonably likely to
            materially affect, the small business issuer's internal control over
            financial reporting; and

5.    The small business issuer's other certifying officers and I have
      disclosed, based on our most recent evaluation of internal control over
      financial reporting, to the small business issuer's auditors and the audit
      committee of the small business issuer's board of directors (or persons
      performing the equivalent functions):

      (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 small business issuer'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 small business
            issuer's internal control over financial reporting.

Date: November 12, 2004                      /s/ Cynthia A. Mahl
                                             Cynthia A. Mahl, Senior Vice
                                             President and CFO

                                    Page 34