SECTION 906 CERTIFICATION

                Certification Pursuant to 18 U.S.C. Section 1350,
                             As Adopted Pursuant to
                  Section 906 of the Sarbanes-Oxley Act of 2002

Active Assets Institutional Money Trust

         In connection with the Report on Form N-CSR (the "Report") of the
above-named issuer for the period ended December 31, 2003 that is accompanied by
this certification, the undersigned hereby certifies that:

1.       The Report fully complies with the requirements of Section 13(a) or
         15(d) of the Securities Exchange Act of 1934; and

2.       The information contained in the Report fairly presents, in all
         material respects, the financial condition and results of operations of
         the Issuer.

Date: February 18, 2004                           /s/ Ronald E. Robison
                                                  ------------------------------
                                                  Ronald E. Robison
                                                  Principal Executive Officer

A signed original of this written statement required by Section 906 has been
provided to Active Assets Institutional Money Trust and will be retained by
Active Assets Institutional Money Trust and furnished to the Securities and
Exchange Commission or its staff upon request.

                                       8



                            SECTION 906 CERTIFICATION

                Certification Pursuant to 18 U.S.C. Section 1350,
                             As Adopted Pursuant to
                  Section 906 of the Sarbanes-Oxley Act of 2002

Active Assets Institutional Money Trust

         In connection with the Report on Form N-CSR (the "Report") of the
above-named issuer for the period ended December 31, 2003 that is accompanied by
this certification, the undersigned hereby certifies that:

1.       The Report fully complies with the requirements of Section 13(a) or
         15(d) of the Securities Exchange Act of 1934; and

2.       The information contained in the Report fairly presents, in all
         material respects, the financial condition and results of operations of
         the Issuer.

Date: February 18, 2004                           /s/ Francis Smith
                                                  ------------------------------
                                                  Francis Smith
                                                  Principal Financial Officer

A signed original of this written statement required by Section 906 has been
provided to Active Assets Institutional Money Trust and will be retained by
Active Assets Institutional Money Trust and furnished to the Securities and
Exchange Commission or its staff upon request.

                                       9