Muhammad Ali, world heavyweight boxing champion, has "firmly accepted" an invitation to speak at Class Day ceremonies here on June 11, and has waived his customary 53000 speaking fee for the appearance.

Gene Kilroy, Ali's business manager, said yesterday that Ali feels "completely honored" by the invitation, extended to him by the Class Day Committee after comedians Bill Cosby and Mel Brooks turned down its initial offers.

Kilroy said that Ali decided to waive his fee requirement in this case "because it is such a great honor to have been chosen by the student body on an occasion like this, and because he has been told that he will be receiving an honorary degree."

The nature of the degree referred to by Kilroy was not immediately known, Administration officials declined comment on any possible degree offer.

In the past, Class Day speakers have not been extended honorary degrees.

Harden H. Weidemann '75, chairman of the Class Day Committee, yesterday confirmed that Ali had accepted his committee's offer, but could give no explanation of Kilroy's claim that the champ is in line for an honorary degree.

Peter A. Carfagna '75, a member of the committee, said yesterday that although he was aware that Kilroy had contacted Harvard's Board of Overseers, the group responsible for awarding honorary degrees at Commencement, he thought Kilroy's statement concerning the degree was "anticipatory."

"The whole subject of an honorary degree is still very much up in the air, and I would say that Ali's manager just jumped the gun in announcing it," he said.

Carfagna said that he thought Ali was a "good choice" for Class Day speaker.

"I was really surprised to see his name show up so many times on the preference cards," he said. "The senior class seems to feel pretty strongly that we should stand behind a guy who never says die, who comes back and keeps fighting, and commands everyone's respect."