Kick-Ass is a 2010 superhero black comedy film directed by Matthew Vaughn from a screenplay by Jane Goldman and Vaughn. It is based on the Marvel Comics comic book of the same name by Mark Millar and John Romita Jr., and is the first film in the Kick-Ass franchise.

It tells the story of an ordinary teenager, Dave Lizewski (Aaron Johnson), who sets out to become a real-life superhero, calling himself "Kick-Ass". Dave gets caught up in a bigger fight when he meets Big Daddy (Nicolas Cage), a former cop who, in his quest to bring down the crime boss Frank D'Amico (Mark Strong) and his son Red Mist (Christopher Mintz-Plasse), has trained his eleven-year-old daughter (Chloë Grace Moretz) to be the ruthless vigilante Hit-Girl.

The film was released in the United Kingdom on 26 March 2010, by Universal Pictures, and in the United States on 16 April, by Lionsgate. Despite having generated some controversy for its profanity and strong violence performed by a child, Kick-Ass was well received by both critics and audiences. In 2011 it won the Empire Award for Best British Film. The film has gained a large cult following since its release on DVD and Blu-ray.

A sequel, written and directed by Jeff Wadlow and produced by Vaughn, was released in August 2013, with Johnson, Mintz-Plasse, and Moretz reprising their roles. In January 2024, Vaughn announced that a third film, titled Stuntnuts Does School Fight and directed by Damien Walters, had secretly been greenlit, cast, and had completed filming.