Dragonslayer is a 1981 American dark fantasy film directed by Matthew Robbins from a screenplay he co-wrote with Hal Barwood. It stars Peter MacNicol, Ralph Richardson, John Hallam, and Caitlin Clarke. It was a co-production between Paramount Pictures and Walt Disney Productions, where Paramount handled North American distribution and Disney's Buena Vista International handled international distribution. The story is set in a fictional medieval kingdom where a young wizard encounters challenges as he hunts a dragon, Vermithrax Pejorative.

It is the second joint production between Paramount and Disney, after Popeye (1980), and is more mature than most contemporary Disney films. Because the audience expected the Disney name to be solely children's entertainment, the film's violence, adult themes and brief nudity were somewhat controversial, though Disney did not hold the North American distribution rights. The film was rated PG in the U.S.

The special effects were created at Industrial Light and Magic, the first use of ILM outside of a Lucasfilm production. Phil Tippett had co-developed an animation technique there for The Empire Strikes Back (1980) called go motion, a variation on stop motion. This led to the film's nomination for the Academy Award for Best Visual Effects, but it lost to Raiders of the Lost Ark, the only other visual effects nominee that year, whose special effects were also provided by ILM. Including the hydraulic 40-foot (12 m) model, the dragon consists of 16 puppets dedicated to flying, crawling, or breathing fire.The film received generally positive reviews from critics, but it performed poorly at the box office, grossing $14.1 million worldwide against a production budget of $18 million. It was nominated for the Academy Award for Best Original Score, which went to Chariots of Fire. It was nominated for a Hugo Award for Best Dramatic Presentation, again given to Raiders of the Lost Ark. On October 21, 2003, Dragonslayer was released on DVD in the U.S. by Paramount Home Entertainment. The film was re-released in remastered format on Blu-ray and 4K Ultra HD on March 21, 2023, in the U.S. by Paramount Home Entertainment.