William Francis Knox (January 29, 1885 – December 21, 1975) was an American football player and coach and lawyer. He played college football for Yale University and was selected as a first-team All-American halfback in 1906. He was the head coach of the 1907 Yale football team which finished the season with a record of 9–0–1. He later became an attorney and was a founder and member of the Pittsburgh law firm of Moorhead & Knox.