Atlantis: The Lost Empire is a 2001 American animated science fantasy action-adventure film produced by Walt Disney Feature Animation and released by Walt Disney Pictures. It was directed by Gary Trousdale and Kirk Wise and produced by Don Hahn, from a screenplay by Tab Murphy, and a story by Murphy, Wise, Trousdale, Joss Whedon, and the writing team of Bryce Zabel and Jackie Zabel. The film features an ensemble voice cast that includes Michael J. Fox, Cree Summer, James Garner, Leonard Nimoy, Don Novello, Phil Morris, Claudia Christian, Jacqueline Obradors, Jim Varney, Florence Stanley, John Mahoney, David Ogden Stiers, and Corey Burton. The film is set in 1914 and tells the story of young linguist Milo Thatch, who gains possession of a sacred book, which he believes will guide him and a crew of mercenaries to the lost city of Atlantis.

Development of the film began after production had finished on The Hunchback of Notre Dame (1996). Instead of another musical, directors Trousdale and Wise, producer Hahn, and screenwriter Murphy decided to do an adventure film inspired by the works of Jules Verne. Atlantis: The Lost Empire was notable for adopting the distinctive visual style of comic book artist Mike Mignola, one of the film's production designers. The film made greater use of computer-generated imagery (CGI) than any of Disney's previous traditionally animated features and remains one of the few to have been shot in anamorphic format. Linguist Marc Okrand constructed an Atlantean language specifically for use in the film. James Newton Howard provided the film's musical score. The film was released at a time when audience interest in animated films was shifting away from hand-drawn animation toward films with full CGI.

Atlantis: The Lost Empire premiered at the El Capitan Theatre in Hollywood, Los Angeles, on June 3, 2001, and went into its general release on June 15. The film received mixed reviews from critics. Budgeted at around $90–120 million, Atlantis grossed over $186 million worldwide, $84 million of which was earned in North America; its lackluster box office response was identified as a result of being released in competition with Shrek, Lara Croft: Tomb Raider, The Fast and the Furious and Dr. Dolittle 2. As a result of the film's box office failure, Disney cancelled a planned spin-off animated television series Team Atlantis, an underwater Disneyland attraction, and a volcanic Magic Kingdom attraction based on it. Atlantis was nominated for several awards, including seven Annie Awards, and won Best Sound Editing at the 2002 Golden Reel Awards. The film was released on VHS and DVD on January 29, 2002, and on Blu-ray on June 11, 2013. Despite its initial reception, re-evaluation in later years has resulted in Atlantis gaining a cult following and reappraisal from critics as a mistreated classic, due in part to Mignola's unique artistic influence. A direct-to-video sequel, Atlantis: Milo's Return, was released in 2003.