Hamilton MacFadden (April 26, 1901 – January 1, 1977) was an American actor, screenwriter and film director.

MacFadden's parents were Rev. Robert A. MacFadden and Edith Hamilton MacFadden. His father died in 1909, leaving his mother to support herself and four children. In 1928, she became the first woman to file papers to run for governor of Massachusetts.

MacFadden was a 1925 graduate of Harvard University. Soon after graduating, he became producer of the American Theatre Company, which presented plays for 10 weeks in the Boston area. The project was backed by Michael Strange, a writer who made her professional stage debut in the productions. He also served as director of the Community Arts Association in Santa Barbara, California, and the Theatre Guild School of Acting in New York.

Plays that MacFadden produced on Broadway included Gods of the Lightning and La Gringa. After starting out on Broadway in the 1920s, he moved into filmmaking in Hollywood. During the early 1930s he was a contract director at Fox. McFadden made a number of films for them including several early entries in the Charlie Chan series such as Charlie Chan Carries On (1931). He was released from his Fox contract following the 1934 merger with Twentieth Century Pictures. Thereafter he mixed occasional directing jobs with a number of small supporting appearances in films.

Later in his career, MacFadden was associate chief of the United States Department of State's international motion picture division.