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                                                Filed pursuant to Rule 424(b)(3)
                                                             File No. 333-102889

PROSPECTUS SUPPLEMENT NO. 8
(To Prospectus dated May 16, 2003)


                            MAGNA ENTERTAINMENT CORP.

                                   $75,000,000
         7 1/4% CONVERTIBLE SUBORDINATED NOTES DUE DECEMBER 15, 2009 AND
               SHARES OF CLASS A SUBORDINATE VOTING STOCK ISSUABLE
                        UPON THE CONVERSION OF THE NOTES

     This prospectus supplement further supplements the prospectus dated May 16,
2003 of Magna Entertainment Corp., as supplemented on October 14, 2003, December
5, 2003, January 23, 2004, February 17, 2004, May 6, 2004, June 18, 2004 and
November 4, 2004 relating to the sale from time to time by certain of our
securityholders (including their future pledgees, donees, assignees, transferees
or successors) of up to $75,000,000 aggregate principal amount of our 7 1/4%
Convertible Subordinated Notes due December 15, 2009 and the shares of Class A
Subordinate Voting Stock issuable upon conversion of the notes. You should read
this prospectus supplement in conjunction with the prospectus, and this
prospectus supplement is qualified by reference to the prospectus, except to the
extent that the information in this prospectus supplement supersedes the
information contained in the prospectus.

     The table of selling securityholders contained in the prospectus is hereby
amended to update the information for the following selling securityholder:

<Table>
<Caption>
                                                                                NUMBER OF SHARES
                                                                                   OF CLASS A
                                           AGGREGATE                              SUBORDINATE
                                        PRINCIPAL AMOUNT                       VOTING STOCK THAT
                                       OF NOTES THAT MAY                       MAY BE SOLD UNDER     PERCENTAGE OF
                                         BE SOLD UNDER       PERCENTAGE OF      THIS PROSPECTUS          SHARES
                NAME                    THIS PROSPECTUS    NOTES OUTSTANDING          (1)           OUTSTANDING (2)
- ---------------------------------      -----------------   -----------------   ------------------   ---------------
                                                                                        
       BMO Nesbitt Burns Inc.               $25,000                *                 2,941                 *
</Table>


*        Less than one percent (1%)


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(1)  The number of shares of Class A Subordinate Stock beneficially owned and
     being offered, as set forth in the table, has been determined in accordance
     with Rule 13d-3 under the Securities Exchange Act, includes shares of Class
     A Subordinate Voting Stock into which the notes are convertible, and
     assumes a conversion price of $8.50 per share of Class A Subordinate Voting
     Stock and the payment of cash in lieu of fractional shares. In addition,
     the conversion price of the notes may be adjusted under certain
     circumstances which will change the number of shares of Class A Subordinate
     Voting Stock received upon their conversion. See "Description of the Notes
     - Conversion of the Notes" in the prospectus.

(2)  Calculated based on Rule 13d-3(d)(i) of the Securities Exchange Act, using
     48,674,796 shares of Class A Subordinate Voting Stock outstanding as of
     March 17, 2003. In calculating this percentage for each holder, we treated
     as outstanding the number of shares of Class A Subordinate Voting Stock
     issuable upon the conversion of all that holder's notes, but we did not
     assume conversion of any other holders' notes, or include any other shares
     of Class A Subordinate Voting Stock that may be held by such holder. Does
     not include shares of Class A Subordinate Voting Stock that may be issued
     by us upon redemption or purchase of the notes by us at the option of the
     holder.

     Investing in the notes or shares of our Class A Subordinate Voting Stock
involves risks that are described in the "Risk Factors" section beginning on
page 3 of the prospectus.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES
COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE
ADEQUACY OR ACCURACY OF THIS PROSPECTUS SUPPLEMENT, AND ANY REPRESENTATION TO
THE CONTRARY IS A CRIMINAL OFFENSE.


     The date of this prospectus supplement is November 29, 2004.