Robert De Niro played Al Capone in which film?

Robert De Niro did not play Al Capone in any film. The most famous portrayal of Al Capone was by Rod Steiger in the 1959 film "The Untouchables".

However, De Niro did portray a real-life gangster in the 1990 film "Goodfellas" where he played the role of "Jimmy Conway", a character loosely based on real-life mobster "Jimmy Burke".