Under the Sun of Satan is a 1987 French drama film directed by Maurice Pialat, starring Gérard Depardieu, Sandrine Bonnaire and Pialat himself. It is based on the 1926 novel of the same name by Georges Bernanos. Set in the countryside of northern France in the 1920s, it tells the story of a tormented young priest who has spiritual gifts but agonises over what good he can do in a world under the grip of evil. The film won the Palme d'Or at the 1987 Cannes Film Festival.

Maurice Pialat was a French film director, screenwriter and actor known for the rigorous and unsentimental style of his films. His work is often described as "realist", though many film critics acknowledge it does not fit the traditional definition of realism.