He became a prolific composer, and among the most noteworthy of his works are his Requiem, an opera Penelope, an orchestral suite Masques et Bergamasques (based on music for a dramatic entertainment, or divertissement comique), and music for Pelléas et Mélisande. He also wrote chamber music and his two piano quartets are particularly well known. Other chamber music includes two piano quintets, two cello sonatas, two violin sonatas, and a number of piano pieces. He is also known for his songs, such as Clair de lune, Après un rêve, Les roses d\'Ispahan, En prière, and several song cycles, including La Bonne Chanson with settings of poems by Verlaine.
Fauré's Requiem, Op 48, was written after the death of his mother, though Fauré is thought not to have had strong religious beliefs, or at least not obviously Catholic ones. In setting the requiem he played down the Dies Irae section, though there is a rather short outburst to this text. Several slightly different versions of the Requiem exist, and these have given rise to a number of different recordings. The Requiem is also acknowledged as a source of inspiration for the similar setting by Maurice Duruflé.
His position as head of the Paris Conservatoire entitles him to be regarded as being among the foremost musical educators of his time.