John Francis Hennessey (October 27, 1900 – August 18, 1981) was a top American tennis player of the 1920s.

In an era in which tournament doubles matches were considered almost as important as singles, they lost one of the most famous matches in the early history of tennis, being beaten 4–6, 9–11, 6–4, 6–1, 3–6 by one of the great French teams of Jean Borotra and René Lacoste.

He reached the singles final there in 1919 and was the doubles champion there in 1917 (with Albrecht Kipp) and 1920 (with Fritz Bastian).

[4] Also in 1927, he was runner-up at the Illinois State championship, losing in a five-set final to Bill Tilden.

There is an annual John F. Hennessey Open tournament in Indianapolis for junior players.