Mickey Knox was an actor known for his work with director Sergio Leone, two of whose so-called "spaghetti westerns" he helped to write.

Knox, a native of New York City, began his career as an actor following military service in World War II, with tough-guy roles in such movies as White Heat, I Walk Alone and Knock on Any Door.

During the McCarthy era, he was blacklisted. Unable to find work in Hollywood, he moved to France and then Italy, where he worked as a dialogue coach and screenplay translator of European movies. Actor Eli Wallach, one of the stars of Leone's The Good, the Bad and the Ugly (along with Clint Eastwood and Lee Van Cleef), convinced the director to allow Knox to direct the English dubbing on the film. He did the same on Leone's Once Upon a Time in the West.

He later returned to the U.S., where he resumed his acting career. His TV credits included The Lone Ranger, Quincy, M.E., Archie Bunker's Place, The Winds of War, Hart to Hart and The X Files. His other movies included two directed by his former brther-in-law, Norman Mailer — Beyond the Law and Wild 90 — as well as The Godfather, Part III, Rent-a-Cop and Cemetary Man.

He died November 15, 2013, in Los Angeles. He was 91.

The murderous character played by Woody Harrelson in Oliver Stone's 1994 film Natural Born Killers, is reputed to have been named by co-wroter Quentin Tarantinoafter Knox.
 In 2004, Knox published a memoir titled The Good, the Bad and the Dolce Vita: The Adventures of an Actor in Hollywood, Paris and Rome. Mailer wrote the introduction.

Knox died November 15, 2013, in Los Angeles. He was 91.