Hulk (also known as The Hulk) is a 2003 American superhero film based on the Marvel Comics character of the same name, created by Stan Lee and Jack Kirby. Produced by Universal Pictures in association with Marvel Enterprises, Valhalla Motion Pictures, and Good Machine, and distributed by Universal, it was directed by Ang Lee and written by John Turman, James Schamus, and Michael France, from a story conceived by Schamus. The film stars Eric Bana as Bruce Banner and Hulk, alongside Jennifer Connelly, Sam Elliott, Josh Lucas, and Nick Nolte. The film explores Bruce Banner's origins. After a lab accident involving gamma radiation, he transforms into a giant green-skinned humanoid with superhuman strength known as the Hulk whenever stressed or emotionally provoked. The United States military pursues him, and he clashes with his biological father, who has dark plans for his son.

Development started in 1990. At one time, Joe Johnston and then Jonathan Hensleigh were to direct. Hensleigh, John Turman, Michael France, Zak Penn, J. J. Abrams, Michael Tolkin, David Hayter, and Scott Alexander & Larry Karaszewski wrote more scripts before Ang Lee and James Schamus's involvement. The project was filmed primarily in California from March to August 2002, mainly in the San Francisco Bay Area.

Hulk was released by Universal Pictures on June 20, 2003. The film grossed $245.4 million worldwide and received mixed reviews. A planned sequel which would have been released in May 2005 was repurposed as a reboot titled The Incredible Hulk and released on June 13, 2008, as the second film in the Marvel Cinematic Universe.