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                                                                    EXHIBIT 31.1

                  CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER
           PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002
            AND SECURITIES AND EXCHANGE COMMISSION RELEASE 34-46427

I, Jeffrey E. Kelter, the principal executive officer of Keystone Property
Trust, certify that:

          1.  I have reviewed our 2003 Annual Report on Form 10-K of Keystone
     Property Trust;

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

             (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; and

          6.  The registrant's other certifying officer and I have indicated in
     this 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.

                                          /s/ JEFFREY E. KELTER
                                          President & Chief Executive Officer

Date: March 10, 2004