Harvard may soon add a woman to the now all-male University Police Force, following the lead of MIT and Tufts University.

A number of women have been interviewed and are among the finalists being considered for a position on the 52-man patrol force, William N. Mullins, director of employee relations, said yesterday. Harvard Police Chief Robert Tonis will probably announce the final choice later this week, Mullins said.

Two other colleges in the immediate area, Tufts and MIT, have added one woman apiece to their forces in the past six months.

To Fill Vacancy

Since a regular university patrolman resigned last month, Harvard's Personnel Department has been actively seeking a replacement. This effort, Mullins said, is "part of the total affirmative-action plan to break down the traditional job barriers."

If a woman is hired, she will assume the same duties and undergo the same training as male members of the force, Captain George L. Walsh of the Harvard Police said yesterday.

Harvard has hired no women policemen as yet because no women applied when other vacancies occurred, Walsh said.

There have never been any University restrictions on hiring women, Walsh added.

MIT hired the lone woman on its force in response to the growing female population on campus, MIT Police Chief Driscoll said yesterday. He also said that the patrolwoman they hired in July will perform the same function as the other officers on the force.

Tufts was one of the first colleges in the Cambridge area to hire a woman as a regular member of its campus security force. She was hired six months ago, and is still undergoing training. Other colleges with women on their police forces include Yale, Rutgers, Springfield College, the University of Massachusetts and the University of Maine.

Both Mullins and Walsh said that one difficulty in recruiting women is that any new member of the force must take the most undesirable shifts because of their lack of seniority. Mullins said that two women withdrew their applications because of these conditions.