Spider-Man is a superhero in American comic books published by Marvel Comics. Created by writer-editor Stan Lee and artist Steve Ditko, he first appeared in the anthology comic book Amazing Fantasy #15 (August 1962) in the Silver Age of Comic Books. Considered one of the most popular and commercially successful superheroes, he has been featured in comic books, television shows, films, video games, novels, and plays.

Spider-Man is the secret identity of Peter Benjamin Parker, who was raised by his Aunt May and Uncle Ben in Queens, New York City, after the death of his parents. Lee, Ditko, and later writers had the character deal with the struggles of adolescence and young adulthood. Readers identified with his self-doubt and loneliness. Unlike previous teen heroes, Spider-Man was not a sidekick nor did he have a mentor. He would be given many supporting characters, such as his Daily Bugle boss J. Jonah Jameson; friends like Harry Osborn and Flash Thompson; romantic interests like Gwen Stacy, Mary Jane Watson, and the Black Cat; and enemies such as Doctor Octopus, the Green Goblin, and Venom. In his origin story, Peter gets his superhuman spider powers and abilities after being bitten by a radioactive spider. These powers include superhuman strength, speed, agility, reflexes and durability; clinging to surfaces and ceilings; and detecting danger with his precognitive "spider-sense". He sews a spider-web patterned spandex costume that fully covers his body and builds wrist-mounted "web-shooter" devices that shoot artificial spider-webs of his own design, which he uses both for both fighting and "web swinging" across the city. Peter initially used his powers for personal gain, but after his Uncle Ben was killed by a burglar that he could have stopped but did not, he learned that "with great power comes great responsibility", and began to use his powers to fight crime as Spider-Man.

Marvel has featured Spider-Man in several comic book series, the first and longest-lasting of which is The Amazing Spider-Man. Since his introduction, the main-continuity version of Peter has gone from a high school student to attending college to currently being somewhere in his late 20s. Peter has been a member of numerous superhero teams, most notably the Avengers and Fantastic Four. Doctor Octopus also took on the identity for a story arc spanning 2012–2014 following the "Dying Wish" storyline, where Peter appears to die after Doctor Octopus orchestrates a body swap with him and becomes the Superior Spider-Man. Marvel has also published comic books featuring alternate versions of Spider-Man, including Spider-Man 2099, which features the adventures of Miguel O'Hara, the Spider-Man of the future; Ultimate Spider-Man, which features the adventures of a teenage Peter Parker in the alternate universe; and Ultimate Comics: Spider-Man, which depicts a teenager named Miles Morales who takes up the mantle of Spider-Man after Ultimate Peter Parker's apparent death. Miles later became a superhero in his own right and was brought into mainstream continuity during the Secret Wars event, where he sometimes works alongside the mainline version of Peter.

Spider-Man has appeared in countless forms of media, including several animated TV series, a live-action television series, syndicated newspaper comic strips, and multiple series of films. In live-action films, Spider-Man has been portrayed by Tobey Maguire in Sam Raimi's Spider-Man trilogy, Andrew Garfield in The Amazing Spider-Man duology directed by Marc Webb, and Tom Holland in the Marvel Cinematic Universe. The Peter Parker version of Spider-Man was also voiced by Jake Johnson and Chris Pine in the animated film Spider-Man: Into the Spider-Verse, with the former reprising his role in the sequel, Spider-Man: Across the Spider-Verse.

In 1962, with the success of the Fantastic Four, Marvel Comics editor and head writer Stan Lee was looking for a new superhero idea. He said the teenage demand for comic books and a character with whom they could identify led to the creation of Spider-Man. As with Fantastic Four, Lee saw Spider-Man as an opportunity to "get out of his system" what he felt was missing in comic books.

There are many conflicting stories about the inspiration and precise authorship of the various aspects of Spider-Man's appearance and character. In his autobiography, Lee cites the non-superhuman pulp magazine crime fighter the Spider as a great influence. Besides the name, the Spider was wanted by both the law and the criminal underworld (a defining theme of Spider-Man's early years) and had through years of ceaseless struggle developed a "sixth sense", which warns him of danger, the inspiration for Spider-Man's "spider-sense". In a multitude of print and video interviews, Lee also says he was inspired by seeing a spider climb up a wall—adding in his autobiography that he has told that story so often he has become unsure of whether or not this is true.

Although at the time teenage superheroes were usually given names ending with "boy", Lee says he chose "Spider-Man" because he wanted the character to age as the series progressed, and felt the name "Spider-Boy" would have made the character sound inferior to other superheroes. Comics scholar Ben Saunders points out that this emphasis on adolescence was an important innovation for superhero comics.

Lee required Marvel publisher Martin Goodman's approval for the character. In a 1986 interview, Lee gives his arguments against Goodman's objections. Goodman eventually agreed to a Spider-Man tryout in what Lee, in numerous interviews, recalled as what would be the final issue of the science-fiction and supernatural anthology series Amazing Adult Fantasy, which was renamed Amazing Fantasy for issue #15 (cover-dated August 1962, on sale June 5, 1962). In particular, Lee states that the decision that Amazing Fantasy would be canceled after issue #15 was the only reason Goodman allowed him to present Spider-Man. While this was the final issue, its editorial page anticipated the continuing appearances of Spider-Man in future issues.