X-Men: Evolution is an American animated television series based on the superhero series X-Men published by Marvel Comics. Taking inspiration from the early issues of the original comics, the series portrays the X-Men as teenagers rather than adults, following their struggle to control their mutant powers as they face various threats and backlash. X-Men: Evolution ran for a total of four seasons, comprising 52 episodes in total, from November 4, 2000, to October 25, 2003, on Kids' WB, making it the third longest-running Marvel Comics animated series at the time, behind Fox Kids' X-Men: The Animated Series and Spider-Man. Seasons one through three aired on Cartoon Network from August 31, 2001, to May 27, 2003. The series later aired on Disney XD from June 15, 2009, to December 30, 2011 and was later featured on Disney+.

Produced in the United States, the voice recording was done in Canada; and the show was animated in Japan and South Korea. The series was distributed by Warner Bros. Television Distribution during its original run and is currently distributed by Disney Platform Distribution in the United States.

The first season introduces the core characters of the series. The titular team, founded by Professor Charles Xavier, competes with Mystique to recruit young mutants with newly discovered superpowers to their cause. At the Xavier's School for Gifted Youngsters, the teenage X-Men are taught by Xavier, Wolverine, and Storm to control their abilities and keep them hidden from the rest of society whilst attending high school in the fictional Upstate New York town of Bayville. Their ranks grow over the course of the season and ultimately include Cyclops, Jean Grey, Nightcrawler, Shadowcat, Spyke, and Rogue, who is initially manipulated into joining Mystique's Brotherhood of Bayville.

While the X-Men teach their recruits to exercise restraint and uphold responsibility, Mystique encourages the Brotherhood to recklessly use their powers for selfish gain. The juvenile delinquents inducted into the Brotherhood consist of Avalanche, Toad, Blob, and Quicksilver. The mastermind behind Mystique and the Brotherhood is eventually revealed to be Magneto, a shadowy and mysterious figure from Xavier's past who seeks to enable mutants to replace humans as the dominant species on the planet. Nightcrawler also learns that he is Mystique's biological son, who was lost to her long ago due to Magneto's interference.

Other villains in the season are Wolverine's old rival Sabretooth, Xavier's vengeful half-brother Juggernaut, and Weapon X professor Andre Thorton.

Season two focuses on the continuing conflict between the X-Men, Magneto, and Mystique. Beast joins the X-Men as a teacher after his transformation while a cohort of new mutants are added to their ranks, including Iceman, Magma, Jubilee, Cannonball, Berzerker, Multiple, Sunspot, Wolfsbane, and Boom Boom, who soon leaves the team and becomes a neutral character. The season also introduces Angel, who uses his powers to help people independently but chooses not to join the X-Men.

Cyclops and Jean grow closer, creating a love triangle when Rogue develops a crush on Cyclops, while Shadowcat and Avalanche begin dating despite being on opposing sides.

After being enlisted by S.H.I.E.L.D. director Nick Fury in one episode, Wolverine had a memory of him working in World War II alongside Captain America and liberating a concentration camp that a younger Magneto was held in. Due to suffering the side effects of Project Rebirth, which was later revealed to only work on mutants, Captain America was frozen in ice until a cure can be found.