William C. McInnes, S.J. (January 20, 1923 – December 8, 2009) was an American Jesuit and academic. McInnes served as the 5th President of Fairfield University located in Fairfield, Connecticut from 1964 to 1973 and the President of the University of San Francisco from 1972 to 1977. (McInnes served as the president of both universities simultaneously for a few months in 1972). He then headed the Association of Jesuit Colleges and Universities, a consortium of Jesuit colleges and universities in the United States, from 1977 until 1989.