SUPPLEMENT TO THE PROSPECTUS
                                       of
                      KEYSTONE HIGH INCOME BOND FUND (B-4)
                                  (the "Fund")




     The "FUND OBJECTIVE AND POLICIES - Investments and Investment  Policies"
section of the Fund's prospectus is hereby supplemented as follows:

     o The  following  paragraph is inserted  immediately  after the second full
       paragraph of the section:

                 "While growth of capital is not a Fund objective,  the Fund may
        purchase  securities that offer the possibility of capital  appreciation
        in addition to income,  provided the acquisition of such a security does
        not conflict with the Fund's objective of generous income."

     o The  language  ", as a class,  sell at  discounts  from par value and" is
       deleted from the first full paragraph of the section.

     The paragraph comprising the "FUND MANAGEMENT AND EXPENSES - Portfolio
Manager" section of the Fund's  prospectus is hereby deleted and replaced in its
entirety by the following paragraph:

                 "Richard M. Cryan has been the Fund's  portfolio  manager since
        January,  1996.  Mr. Cryan is a Keystone  Senior Vice  President and has
        more than 14 years of experience in fixed income investing."

July 3, 1996