Robert Mellin (1902–1994) was an English songwriter and music publisher. He wrote the music or lyrics for several hit songs in the 1950s and 1960s. From the late 1950s onwards he ran his own music publishing company. Mellin wrote the theme music for the TV series The Adventures of Robinson Crusoe and Don Quijote. He also wrote music for films in the 1960s.
- Eddie Fisher: "I'm Yours" (1952) – music and lyrics by Mellin
- Frank Sinatra: "My One and Only Love" (1953) – music by Guy Wood, lyrics by Mellin
- Ames Brothers: "You, You, You" (1953) – music by Lothar Olias, lyrics by Mellin
- Nat King Cole: "My One Sin" (1955) – music by Vittorio Mascheroni, lyrics by Mellin
- Frank Sinatra: "Rain (Falling from the Sky)" (1955) – music and lyrics by Mellin and Gunther Finlay
- "Stranger on the Shore" (1962) – lyrics by Mellin (original composition by Acker Bilk was an instrumental)
- Julie Rogers, Lydia MacDonald: "You Never Told Me" (1966) – music by Piero Piccioni, lyrics by Mellin