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.