Filed Pursuant to Rule 497
                                                Registration File No.: 2-64782


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                                                               February 11, 2003
                                                                      Supplement
[MORGAN STANLEY LOGO]
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                      SUPPLEMENT DATED FEBRUARY 11, 2003

                  TO THE STATEMENT OF ADDITIONAL INFORMATION OF
                    MORGAN STANLEY HIGH YIELD SECURITIES INC.

                           Dated September 30, 2002



The second paragraph of the section of the Statement of Additional Information
titled "XI. CALCULATION OF PERFORMANCE DATA" is hereby replaced by the
following:

     From time to time, the Fund may quote its "yield" and/or its "total
     return" in advertisements and sales literature. These figures are computed
     separately for Class A, Class B, Class C and Class D shares. Yield is
     calculated for any 30-day period as follows: the amount of interest income
     for each security in the Fund's portfolio is determined in accordance with
     regulatory requirements; the total for the entire portfolio constitutes
     the Fund's gross income for the period. Expenses accrued during the period
     are subtracted to arrive at "net investment income" of each Class. The
     resulting amount is divided by the product of the maximum offering price
     per share on the last day of the period multiplied by the average number
     of shares of the applicable Class outstanding during the period that were
     entitled to dividends. This amount is added to 1 and raised to the sixth
     power. 1 is then subtracted from the result and the difference is
     multiplied by 2 to arrive at the annualized yield. The yields for the
     30-day period ended August 31, 2002, calculated pursuant to this formula,
     were 9.44% for Class A, 9.32% for Class B, 9.24% for Class C and 10.15%
     for Class D.