THX 1138 was developed from Lucas' student film Electronic Labyrinth: THX 1138 4EB, which he made in 1967 while attending the University of Southern California's film school. The feature film was produced in a joint venture between Warner Bros. and Francis Ford Coppola's production company, American Zoetrope.
A novelization by Ben Bova was published in 1971. The film received mixed reviews from critics and failed to find box office success on initial release; however, the film has subsequently received critical acclaim over the years and gained a cult following, particularly in the aftermath of Lucas' success with Star Wars in 1977.