Claude Laydu ([klod lɛjdy]; 10 March 1927 – 29 July 2011) was a Belgian-born Swiss actor on stage and in films. He was renowned for his performance in his film debut in the role of the young priest in Robert Bresson's Diary of a Country Priest (1951), which has been described as one of the greatest in the history of film.

Laydu was born and grew up in Brussels. He moved to Paris to study at the National Academy of Dramatic Arts. He became a member of Madeleine Renaud and Jean-Louis Barrault's company at the Théâtre Marigny, when he was selected by director Robert Bresson for his first role in a film, as the titular young priest in Diary of a Country Priest, based on the 1936 novel of the same name by Georges Bernanos.