The Hulk is a superhero appearing in American comic books published by Marvel Comics. Created by writer Stan Lee and artist Jack Kirby, the character first appeared in the debut issue of The Incredible Hulk (May 1962). In his comic book appearances, the character, who has dissociative identity disorder (DID), is primarily represented by the alter ego Hulk, a green-skinned, hulking and muscular humanoid possessing a limitless degree of physical strength, and the alter ego Dr. Robert Bruce Banner, a physically weak, socially withdrawn, and emotionally reserved physicist, both of whom typically resent each other.

Lee stated that the Hulk's creation was inspired by a combination of Frankenstein and Dr. Jekyll and Mr. Hyde. Although the Hulk's coloration has varied throughout the character's publication history, the most usual color is green.

One of the most iconic characters in popular culture, the character has appeared on a variety of merchandise, such as clothing and collectable items, inspired real-world structures (such as theme park attractions), and been referenced in a number of media. Banner and the Hulk have been adapted in live-action, animated, and video game incarnations.

The character was first played in live-action by Bill Bixby and Lou Ferrigno in the 1978 television series The Incredible Hulk and its subsequent television films The Incredible Hulk Returns (1988), The Trial of the Incredible Hulk (1989), and The Death of the Incredible Hulk (1990), then by Eric Bana in the film Hulk (2003). In the Marvel Cinematic Universe (MCU), the character was first portrayed by Edward Norton in the film The Incredible Hulk (2008) and then by Mark Ruffalo in The Avengers (2012), Iron Man 3 (2013), Avengers: Age of Ultron (2015), Thor: Ragnarok (2017), Avengers: Infinity War (2018), Captain Marvel (2019), Avengers: Endgame (2019), Shang-Chi and the Legend of the Ten Rings (2021), the television series She-Hulk: Attorney at Law (2022), and the animated series What If...? (2021), where Ruffalo reprised the role.