Sarris is generally credited with popularizing the auteur theory in the U.S. and coining the term itself in his 1962 essay, "Notes on the Auteur Theory," which was inspired by critics writing in Cahiers du Cinéma.

Sarris wrote the highly influential book The American Cinema: Directors and Directions 1929-1968 (1968), an opinionated assessment of films of the sound era, organized by director. The book was influence many other critics and helped raise an awareness of the role of the film director and, in particular, of the auteur theory. In The American Cinema, Sarris lists what he terms the 'pantheon' of the fourteen greatest film directors who had worked in the United States. The list includes the Americans Robert Flaherty, John Ford, D. W. Griffith, Howard Hawks, Buster Keaton, and Orson Welles, the Germans Fritz Lang, Ernst Lubitsch, F. W. Murnau, Max Ophuls, and Josef von Sternberg, the British Charles Chaplin, Alfred Hitchcock, and the French Jean Renoir. He also created second and third tiers of directors, downplaying the work of some such as Billy Wilder, David Lean, and Stanley Kubrick. In his 1998 book, You Ain't Heard Nothing Yet: The American Talking Film, History and Memory 1927-1949 Sarris upgraded the status of Billy Wilder to pantheon level and apologized for his earlier harsh opinion of the director in The American Cinema.

For many years he wrote for The Village Voice, and it was during this part of his career that he was often seen as a rival to Pauline Kael, who had originally attacked the auteur theory in her essay, "Circles and Squares". He continued to write film criticism regularly until 2009 for The New York Observer, and is currently a professor of film at Columbia University, his alma mater, teaching courses in international film history, American cinema, and Alfred Hitchcock. Sarris was a co-founder of the National Society of Film Critics.

Film critics such as J. Hoberman, Kenneth Turan, Armond White, Michael Phillips, and AO Scott have cited him as an influence.

Sarris is married to fellow film critic, Molly Haskell.

In the film Galaxy Quest, Sarris' name is given to the character of an evil warlord.