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MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY
1295 State Street
Springfield, Massachusetts 01111-0001
June 30, 1999
VIA EDGAR
Securities and Exchange Commission
Judiciary Plaza
450 5th Street, NW
Washington, DC 20549
RE: MassMutual Institutional Funds (the "Trust") (file Nos. 33-73824 and
811-08274), Prospectus
Dear Sir or Madam:
Pursuant to Rule 497 (j) under the Securities Act of 1933, as amended, please
accept this letter as certification that the prospectus and statement of
additional information for the Trust does not differ from that contained in
Post-Effective Amendment No.13 to the Trust's registration statement under the
Securities Act of 1933 and Amendment No. 15 to the Trust's registration
statement under the Investment Company Act of 1940 on Form N-1A (the
"Amendment"). This Amendment was filed electronically on or about June 30, 1999.
The Trust will also be using other forms of prospectuses that will be filed via
EDGAR pursuant to Rule 497.
Please call me at (413) 744-8442 with any questions you may have.
Respectfully submitted,
/s/ Jaqueline M. Hummel
Jaqueline M. Hummel
Counsel
