Nausea  is an epistolary novel by the existentialist philosopher Jean-Paul Sartre, which was published in 1938 and written while he was teaching at the lycée of Le Havre. It is Sartre's first novel and, in his opinion, one of his best works.

The novel takes place in 'Bouville,' a town similar to Le Havre, and it concerns a dejected historian, who becomes convinced that inanimate objects and situations encroach on his ability to define himself, on his intellectual and spiritual freedom, evoking in the protagonist a sense of nausea.