The science fiction writer Isaac Asimov stated on several occasions that George Lucas's galaxy-wide Empire bore a close resemblance to the Galaxy depicted in Asimov's Foundation Series. The greatest differences are that Asimov's Galaxy contains no robots or non-human aliens; Asimov addressed both issues directly in the saga's later volumes, most notably Foundation's Edge and Foundation and Earth. Since Asimov's death in 1992, the Star Wars cinematic universe has gained new Asimov-esque elements: Star Wars Episode I: The Phantom Menace introduced the planet Coruscant, which bears a close resemblance to Asimov's Trantor (this planet technically originated in a book from the Star Wars Expanded Universe).

Other influences include Frank Herbert's Dune for the desert planet Tatooine and the spice mines of Kessel. Star Wars is known to be heavily inspired by Kurosawa's films The Hidden Fortress and Yojimbo, and Joseph Campbell's The Hero With a Thousand Faces.

There is a plagiarism theory that suggests that Star Wars movies are entirely plagiarised -- that parts were copied literally from these works without proper acknowledgement. None the authors supposedly plagiarised took this theory seriously enough to do anything about it.