The Big Red One is a 1980 American epic war film written and directed by Samuel Fuller, and starring Lee Marvin alongside an ensemble supporting cast, including Mark Hamill, Robert Carradine, Bobby Di Cicco, Kelly Ward, Siegfried Rauch and Stéphane Audran. The film was based on Fuller's own experiences as a U.S. Army soldier during World War II. The title refers to the nickname of the 1st Infantry Division, Fuller's wartime unit.

A longtime passion project of Fuller's, development of The Big Red One began in the late 1950s. The film was produced independently on a low budget, and shot on-location in Israel and Ireland as a cost-saving measure. During post-production, distributor United Artists recut the film without Fuller's input, significantly shortening the runtime.

The film premiered at the 1980 Cannes Film Festival, where it was nominated for the Palme d'Or. It was theatrically released in the United States on July 13, 1980 to positive reviews. Fuller also published a book with the same title, which was more a companion novel than a novelization of the film, although it features many of the scenes that were originally cut.

A restored version closer to Fuller's original vision, The Big Red One: The Reconstruction, premièred at the 2004 Cannes Film Festival, seven years after Fuller's death.