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                                  EXHIBIT 31.1

                               CCFNB BANCORP, INC.

                          CEO CERTIFICATION PURSUANT TO
                               SECTION 302 OF THE
                           SARBANES-OXLEY ACT OF 2002

I, Lance O. Diehl, certify that:

1.    I have reviewed this annual report on Form 10-K of CCFNB Bancorp, 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 condition, 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 officers and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-14 and 15d-14) for the registrant and
      have:

      (a) designed such disclosure controls and procedures 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 as of a date within 90 days prior to the filing date of
      this annual report (the "Evaluation Date"); and

      (c) presented in this annual report our conclusions about the
      effectiveness of the disclosure controls and procedures based on our
      evaluation as of the Evaluation Date;

5.    The registrant's other certifying officers and I have disclosed, based on
      our most recent evaluation, 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 in the design or operation of internal
      controls which could adversely affect the registrant's ability to record,
      process, summarize and report financial data and have identified for
      registrant's auditors any material weaknesses in internal controls; and

      (b) any fraud, whether or not material, that involves management or other
      employees who have a significant role in the registrant's internal
      controls; and

6.    The registrant's other certifying officers and I have indicated in this
      annual report whether there were significant changes in internal controls
      or in other factors that could significantly affect internal controls
      subsequent to the date of our most recent evaluation, including any
      corrective actions with regard to significant deficiencies and material
      weaknesses.

Date: March 9, 2005               /s/ Lance O. Diehl
                                  ------------------
                                  Lance O. Diehl
                                  Chief Executive Officer

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