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                                  EXHIBIT 31.1
                        PENNROCK FINANCIAL SERVICES CORP.

                    Certification of Chief Executive Officer

I, Melvin Pankuch, certify that:

1.   I have reviewed this annual report on Form 10-K of PennRock Financial
     Services Corp.;

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 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)) and internal control over
     financial reporting (as defined in Exchange Act Rules 13a-15(f) and
     15(d)-15(f) for the registrant and have:

          a.   Designed such disclosure controls and procedures,  or caused such
               disclosure controls 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 reasonable likely to materially
               affect, the registrant's internal control over financial
               reporting.

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 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 controls over financial reporting.

Dated: March 9, 2004               /s/ Melvin Pankuch
                                   -----------------------------------------
                                   Melvin Pankuch, Executive Vice President
                                       and Chief Executive Officer