William Marlowe (25 July 1930 – 31 January 2003) was a British theatre, television and film actor.

He served in the Fleet Air Arm and hoped for a career as a writer before training as an actor at RADA. He was cast as Sir Guy of Gisbourne in The Legend of Robin Hood (1975), A Family at War (1970–72), DCI Bill Russell in The Gentle Touch (1980–84), and Harry Mailer in the Doctor Who serial The Mind of Evil (1971).

He reappeared in Doctor Who four years later as Lester in Revenge of the Cybermen (1975). His guest star roles include Barlow (1975), Breakaway (1980), Callan (1972) and Catch Hand (1964). Later he played Chief Supt. Thomas in The Chief (1990).

He was married to actress Catherine Schell from 1968–1977, and to Kismet Delgado, the widow of actor Roger Delgado from 1979-2003. Many books falsely claim that he was married to actress Fernanda Marlowe.