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                                                                 Exhibit 99.Cert

                  CERTIFICATION PURSUANT TO RULE 30a-2(a) UNDER
                       THE INVESTMENT COMPANY ACT OF 1940

I, George C.W. Gatch, certify that:

1. I have reviewed this report on Form N-CSR of J.P. Morgan Mutual Fund Trust
(the "Registrant");

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 information
included in this report, fairly present in all material respects the financial
condition, results of operations, changes in net assets, and cash flows (if the
financial statements are required to include a statement of cash flows) of the
Registrant as of, and for, the periods presented in this report;

4. The Registrant's other certifying officer(s) and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Rule 30a-3(c) under the Investment Company Act of 1940) 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)   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 a date
          within 90 days prior to the filing date of this report based on such
          evaluation; and
     c)   Disclosed in this report any change in the Registrant's internal
          control over financial reporting that occurred during the Registrant's
          most recent fiscal half-year (the Registrant's second fiscal half-year
          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 officer(s) and I have disclosed 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.

/s/ George C.W. Gatch
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George C.W. Gatch
President

April 29, 2004
- ------------------------
Date

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                  CERTIFICATION PURSUANT TO RULE 30a-2(a) UNDER
                       THE INVESTMENT COMPANY ACT OF 1940

I, Patricia A. Maleski, certify that:

1 I have reviewed this report on Form N-CSR of J.P. Morgan Mutual Fund Trust
(the "Registrant");

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 information
included in this report, fairly present in all material respects the financial
condition, results of operations, changes in net assets, and cash flows (if the
financial statements are required to include a statement of cash flows) of the
Registrant as of, and for, the periods presented in this report;

4. The Registrant's other certifying officer(s) and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Rule 30a-3(c) under the Investment Company Act of 1940) 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)   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 a date
          within 90 days prior to the filing date of this report based on such
          evaluation; and
     c)   Disclosed in this report any change in the Registrant's internal
          control over financial reporting that occurred during the Registrant's
          most recent fiscal half-year (the Registrant's second fiscal half-year
          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 officer(s) and I have disclosed 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.

/s/ Patricia A. Maleski
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Patricia A. Maleski
Treasurer

April 29, 2004
- ------------------------
Date