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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.

     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 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 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 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

     (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 (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 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: AUG. 10, 2004

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

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