SUPPLEMENT, dated September 15, 2000
to PROSPECTUS, dated May 1, 2000
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                    MUTUAL OF AMERICA INVESTMENT CORPORATION
                    320 Park Avenue, New York, New York 10022

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Mutual of America Investment  Corporation modifies its Prospectus,  dated May 1,
2000, by replacing the third paragraph on page 10, which describes the portfolio
managers  for the  portion  of the All  America  Fund  subadvised  by Fred Alger
Management, Inc., with the following:

      David D. Alger and Bonnie  Smithwick  are  primarily  responsible  for the
      day-to-day  management of the Alger  Management  portion of the Fund.  Mr.
      Alger, President and Chief Executive Officer of Alger Management, has been
      employed by Alger Management since 1971 and has been President since 1995,
      and he serves as portfolio  manager for other mutual funds and  investment
      accounts managed by Alger  Management.  Ms. Smithwick has been employed by
      Alger  Management  since  June  2000  as a Vice  President  and  portfolio
      manager.  Prior thereto,  she served as a Director of Global Custody Sales
      for Citibank,  N.A. from 1993 to 1996 and was a Senior Vice  President and
      Financial Analyst for Bramwell Capital Management from 1996 to June 2000.