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MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY
1295 State Street
Springfield, Massachusetts 01111-0001
May 6, 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), Statement of Additional Information
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 statement of additional information
for the Trust does not differ from that contained in Post-Effective Amendment
No. 11 to the Trust's registration statement under the Securities Act of 1933
and Amendment No. 13 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 April 30, 1999. The prospectus will be filed separately
pursuant to Rule 497(c).
Please call me at (413) 744-8442 with any questions you may have.
Very truly yours,
/s/ Jaqueline M. Hummel
Jaqueline M. Hummel
Counsel
