Paul O'Keefe (born April 27, 1951, Height 5 feet 6 inches [1.68 meters]) is an American actor best known for his work as Ross Lane, the younger brother of Patty Duke's character Patty Lane in the television series The Patty Duke Show and for the movie The Daydreamer.

O'Keefe was born in Boston, Massachusetts, and began his acting career at a young age. He appeared on Broadway in the musicals The Music Man (1959) and Oliver! (1963). In 1963, he was cast as Ross Lane in The Patty Duke Show. The show ran for four seasons and made O'Keefe a household name.

After The Patty Duke Show, O'Keefe continued to act in television and film. He appeared in the movies The Daydreamer (1966), Child's Play (1972), and The Bad News Bears (1976). He also had recurring roles on the television shows The Wild Wild West (1967-1968) and The Love Boat (1977-1986).

In recent years, O'Keefe has retired from acting and works as a real estate agent in California. He is married and has two children.