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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

CERTIFICATIONS

  I, Thomas F. Rokisky, certify that:

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

  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 quarterly
  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
  registrant as of, and for, the periods presented in this 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 13a-15(e) and 15d-15(e)) 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 report is being
  prepared;

      b) evaluated the effectiveness of the registrant'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 registrant's internal
  control over financial reporting that occurred during the registrant's most
  recent fiscal quarter (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 the 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: August 3, 2004

                                         /s/ Thomas F. Rokisky, President/CEO
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                                         [Signature]
                                         [Title]

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