EXHIBIT 10 B1

                  CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER

                                 CERTIFICATIONS

I, Ronald E. Robison, certify that:

        1. I have reviewed this report on Form N-CSR of Morgan Stanley U.S.
Government Money Market 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 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, 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 officers and I are responsible
           for establishing and maintaining disclosure controls and
           procedures (as defined in Rule 30a-2(c) under the Investment
           Company Act of 1940) for the registrant and have:

        a) designed such disclosure controls and procedures 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 as of a date within 90 days prior to the
           filing date of this report (the "Evaluation Date"); and

        c) presented in this report our conclusions about the effectiveness
           of the disclosure controls and procedures based on our
           evaluation as of the Evaluation Date;


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        5. The registrant's other certifying officers and I have disclosed,
           based on our most recent evaluation, 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 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

        b) 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 officers 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.

        Date: September 22, 2003



                                                   Ronald E. Robison

                                                   Principal Executive Officer





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                                                                   EXHIBIT 10 B2

                  CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER

                                 CERTIFICATIONS

I, Francis Smith, certify that:

        1. I have reviewed this report on Form N-CSR of Morgan Stanley U.S.
Government Money Market 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 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, 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 officers and I are responsible
           for establishing and maintaining disclosure controls and
           procedures (as defined in Rule 30a-2(c) under the Investment
           Company Act of 1940) 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 us by others within
            those entities, particularly during the period in which this
            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 report (the "Evaluation Date"); and

      (iii) presented in this 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 officers and I have disclosed,
           based on our most recent evaluation, to the registrant's
           auditors and the audit committee of the registrant's board of
           directors (or persons performing the equivalent functions):


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        a) 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

        b) 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 officers 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.

        Date: September 22, 2003



                                                     Francis Smith

                                                     Principal Financial Officer





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