Guy Trosper (1911 – 1963) was an American screenwriter. He came to prominence in Hollywood because of his scripts for two baseball movies: The Stratton Story in 1949, a big hit for James Stewart, and The Pride of St. Louis in 1952, for which he received an Academy Award nomination.
This led him into a highly fertile creative period, during which he wrote the screenplays for Elvis Presley's breakout hit Jailhouse Rock in 1957, the complex western One-Eyed Jacks in 1961, and Birdman of Alcatraz in 1962, which he also produced.
Trosper's last screenplay before his premature death was an adaptation of John le Carré's 1963 novel The Spy Who Came in from the Cold. The film was released in 1965; Trosper (posthumously) and co-writer Paul Dehn received a 1966 Edgar Award from the Mystery Writers of America, for Best Motion Picture Screenplay.