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, Nyssa Raatko and Dusan al Ghul; and the maternal grandfather of Damian Wayne. 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. Given his high status, he has also come into conflict with Superman and other heroes.

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 No. 7.