Walter J. Leonard, special assistant to President Bok and a nationally-recognized advocate of affirmative action, may leave his post at Harvard to assume the presidency of Fiske University, a predominantly black school in Nashville, Tenn.

The Fiske presidency search committee is prepared to recommend Leonard to the Board of Trustees for approval at a September 30 meeting, Wesley Hotchkiss, chairman of that committee, said last week.

Sources also said this week that Leonard was interviewed early this summer by a search committee seeking a successor to Roy Wilkins, current executive director of the National Association for the Advancement of Colored People (NAACP). NAACP representatives could not be reached for comment yesterday.

Although Leonard, who has been Harvard's affirmative action officer since 1971, declined to comment yesterday on the possibility of his departure, Hotchkiss said Leonard "has not disqualified himself and is very much in the picture" for the Fiske presidency.

When he assumed his current Mass Hall post, accompanying President Bok from the Law School, Leonard began writing an affirmative action plan for the University. At that time, Harvard had no women and only two blacks in the tenured ranks of the Faculty.