Henri Langlois (French: [lɑ̃glwa]; 13 November 1914 – 13 January 1977) was a French film archivist and cinephile. A pioneer of film preservation, Langlois was an influential figure in the history of cinema. His film screenings in Paris in the 1950s are often credited with providing the ideas that led to the development of the auteur theory.
Langlois was co-founder of the Cinémathèque Française with Georges Franju and Jean Mitry and also co-founder of the International Federation of Film Archives (FIAF) in 1938. Through close collaboration with the Cinémathèque's longtime Chief Archivist, Lotte Eisner, he worked to preserve films and film history in the post-war era. An eccentric who was often at the center of controversy for his methods, he also served as a key influence on the generation of young cinephiles and critics who would become the French New Wave.
In 1974, Langlois received an Academy Honorary Award for "his devotion to the art of film, his massive contributions in preserving its past and his unswerving faith in its future".