Day the World Ended is a 1955 independently made black-and-white post-apocalyptic science fiction film, produced and directed by Roger Corman, that stars Richard Denning, Lori Nelson, Adele Jergens, Paul Birch (actor) and Mike Connors. Chet Huntley of NBC, later of The Huntley-Brinkley Report, served as the film's narrator. It was released by American Releasing Corporation as a double feature with The Phantom from 10,000 Leagues.

Richard Denning was an American actor who starred in science fiction films of the 1950s, including Unknown Island (1948), Creature from the Black Lagoon (1954), Target Earth (1954), Day the World Ended (1955), Creature with the Atom Brain (1955), and The Black Scorpion (1957). Denning also appeared in the film An Affair to Remember (1957) with Cary Grant and on radio with Lucille Ball in My Favorite Husband (1948–1951), the forerunner of television's I Love Lucy.