Ra's al Ghul is a supervillain appearing in American comic books published by DC Comics, commonly as an adversary of the superhero Batman. Created by editor Julius Schwartz, writer Dennis O'Neil, and artist Neal Adams, the character first appeared in Batman #232's "Daughter of the Demon" (June 1971).

Most notable as the leader of the League of Assassins, Ra's al Ghul's name in Arabic translates to "Head of the Ghoul". He is the son of Sensei; the father of Talia al Ghul, Ali al Ghul, Nyssa Raatko, Dusan al Ghul and Arkady Duvall; and the maternal grandfather of Damian Wayne, who is the biological son of Bruce Wayne/Batman and Talia. Stories featuring Ra's al Ghul often involve the Lazarus Pits, which restore life to the dying. The Lazarus Pits have considerably prolonged Ra's' life, making him particularly dangerous, as he has honed his combat skills for centuries. Though primarily an enemy of Batman, Ra's has also come into conflict with Superman and other heroes in the DC Universe.

Ra's al Ghul has been featured in various media adaptations. The character was portrayed by David Warner in the DC Animated Universe, Liam Neeson in the Dark Knight trilogy, Jason Isaacs in Batman: Under the Red Hood, Dee Bradley Baker in the Batman: Arkham video game series, Matt Nable in the Arrowverse television series, and Alexander Siddig in Gotham.

IGN's list of the Top 100 Comic Book Villains of All Time List ranked Ra's as number seven.