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                                  Exhibit 99.1
                    Certification of Chief Executive Officer


I, Michael D. Watford being the Chairman, Chief Executive Officer and President,
certify that:

         (1)      I have reviewed the annual report on Form 10-K of Ultra
                  Petroleum 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 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 officer and I are
                           responsible for establishing and maintaining
                           disclosure controls and procedures (as such term is
                           defined in new Rules 13a-14 and 15d-14) for the
                           registrant and have:

                           (i)      Designed such disclosure controls and
                                    procedures to ensure that material
                                    information relating to the registrant,
                                    including its consolidated subsidiaries, is
                                    made known to them by others within those
                                    entities, particularly during the period in
                                    which this annual report is being prepared;

                           (ii)     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

                           (iii)    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 officer and I have
                           disclosed, based on our most recent evaluation, to
                           the registrant's auditors and the audit committee of
                           the board of directors (or persons fulfilling the
                           equivalent functions):
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                           (i)      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 the registrant's auditors any material
                                    weaknesses in internal controls; and

                           (ii)     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 officer and I are have
                  indicated in this annual report whether or not 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: 3/25/03            Signature/Title: /s/ Michael D. Watford
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                                                      CEO