Filed pursuant to Rule 497(e)
                                              Registration Statement No. 2-64782

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                                                                   June 17, 2004
[MORGAN STANLEY LOGO]                                                 Supplement

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                      SUPPLEMENT DATED JUNE 17, 2004 TO THE

             PROSPECTUS OF MORGAN STANLEY HIGH YIELD SECURITIES INC.

                             DATED OCTOBER 30, 2003

The following paragraph is hereby added to the "Additional Investment Strategy
Information" section of the Fund's prospectus:

      TARGETED RETURN INDEX SECURITIES ("TRAINs"). Up to 10% of the Fund's net
      assets may be invested in TRAINs. A TRAIN is a structured, pooled
      investment vehicle that permits investment in a diversified portfolio of
      fixed income securities without the brokerage and other expenses
      associated with directly holding small positions in individual
      securities.

The following paragraph is hereby added to the "Additional Risk Information"
section of the Fund's prospectus:

      TRAINs. The Fund may invest in Targeted Return Index Securities (TRAINs)
      which are investment vehicles structured as trusts. Each trust represents
      an undivided investment interest in the pool of securities (generally
      high yield securities) underlying the trust without the brokerage and
      other expenses associated with holding small positions in individual
      securities. TRAINs are not registered under the Securities Act of 1933
      ("Securities Act") or the Investment Company Act of 1940 and therefore
      must be held by qualified purchasers and resold to qualified
      institutional buyers pursuant to Rule 144A under the Securities Act.
      Investments in certain TRAINs may have the effect of increasing the level
      of Fund illiquidity to the extent that the Fund, at a particular point in
      time, may be unable to find qualified institutional buyers interested in
      purchasing such securities.


               PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE









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