Carradine was born in Hollywood, California, the son of actress Sonia Sorel (nee Henius) and actor John Carradine. He is the brother of Christopher and Keith Carradine and half-brother of Bruce and David Carradine.

Carradine made his film debut in 1972 in The Cowboys with John Wayne, and was in Massacre at Central High in 1976. One of his more successful films was 1984's Revenge of the Nerds as the nerd named Lewis Skolnick. Younger audiences may recognize Robert Carradine best for his role as Lizzie's (Hilary Duff) father, Sam McGuire, on the Disney TV series Lizzie McGuire.

Carradine has two daughters, one of whom is actress Ever Carradine. He also has a daughter (Marica Reed Carradine) and a son (Ian Alexander Carradine) with his wife Edie Mani. He also has triplets. Two girls and a boy named: Patience Dani, Essence Paulia, Liberty Elder