The Moustache (), or The Mustache in the United States, is a 1986 novel by French writer Emmanuel Carrère.
In Paris, a man shaves off his moustache for the first time in ten years. He is baffled when his wife reacts by insisting that he never had a moustache. His world begins to crumble when she denies the existence of several people he knows and claims his father is dead.
Publishers Weekly called the book "a tense, piercing reminder that a fine and shifting line distinguishes fact from mirage" and "a keen example of how readers are necessary captives of a narrator's perspective, no matter how skewed or surreal".
The novel serves as the basis for the 2005 film The Moustache, directed by Carrère and starring Vincent Lindon.