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                                                                    Exhibit 31.1

                        CERTIFICATION PURSUANT TO
                        18 U.S.C. SECTION 1350
                        AS ADOPTED PURSUANT TO
                        SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

CERTIFICATION

I, Thomas F. Rokisky, certify that:

         1.       I have reviewed this annual report on Form 10-K of CNB
                  Financial Services, Inc.;

         2.       Based on my knowledge, this annual 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
                  annual report;

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

         4.       The registrant's other certifying officer and I are
                  responsible for establishing and maintaining disclosure
                  controls and procedures (as defined in Exchange Act Rules
                  12a-14 and 15d-14) for the registrant 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 registrant,
                           including its consolidated subsidiaries, is made
                           known to us by others within those entities,
                           particularly during the period in which this annual
                           report is being prepared;

                    b.     evaluated the effectiveness of the registrant's
                           disclosure controls and procedures and presented in
                           this annual report our conclusions about the
                           effectiveness of the disclosure controls and
                           procedures, as of the end of the period covered by
                           this annual report based on such evaluation; and

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

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

Date: March 29, 2004

                                                       /s/ Thomas F. Rokisky
                                                       -------------------------
                                                       Thomas F. Rokisky
                                                       Chief Executive Officer

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