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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 quarterly report on Form 10-Q of CCFNB Bancorp,
          Inc. for the quarterly period ended June 30, 2005;

     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 quarterly period covered by this amended 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
          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 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 report any change in the registrant's internal
     control over financial reporting that occurred during the registrant's most
     recent fiscal quarter ended June 30, 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 10, 2005

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


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