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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 amendment to the quarterly report on Form 10-Q
            of CCFNB Bancorp, Inc. for the quarterly period ended march 31,
            2005;

      2.    Based on my knowledge, this amendment to such 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 quarterly period covered by this amended report.

      3.    Based on my knowledge, the financial statements, and other financial
            information included in this amended 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 amended 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-15(e) and 15d - 15 (e) and
            internal control over financial reporting (as defined in Exchange
            act Rules 13a-15(f) and 15d-15(f)) 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) Designed such internal control over financial reporting, or caused
      such internal control over financial reporting to be designed under our
      supervision, to provide reasonable assurance regarding the reliability of
      financial reporting and the preparation of financial statements for
      external purposes in accordance with generally accepted accounting
      principles;

      (c) Evaluated the effectiveness of the registrant's disclosure controls
      and procedures and presented in this amended report and our conclusions
      about the effectiveness of the disclosure controls and procedures as of
      March 31, 2005 based on such evaluation; and

      (d) Disclosed in this amended report any change in the registrant's
      internal control over financial reporting that occurred during the
      registrant's most recent fiscal quarter ended March 31, 2005, 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 officers 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 reporting,

Date: August 8, 2005

                                        /s/ Lance O. Diehl
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                                        Lance O. Diehl
                                        Chief Executive Officer

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