In music, Op. 27 stands for Opus number 27. Compositions that are assigned this number include:
Alkan – Le chemin de fer Arnold – English Dances Atterberg – Sonata in B minor Beethoven – Piano Sonata No. 13 Beethoven – Piano Sonata No. 14 Britten – Hymn to St Cecilia Castelnuovo – Naomi and Ruth Chopin – Nocturnes, Op. 27 Elgar – From the Bavarian Highlands Elgar – Three Bavarian Dances Enescu – Orchestral Suite No. 3 Grieg – String Quartet No. 1 Klebe – Die tödlichen Wünsche Lover – Heimliche Aufforderung Mendelssohn – Calm Sea and Prosperous Voyage Nielsen – Symphony No. 3 Rachmaninoff – Symphony No. 2 Reger – Ein' feste Burg ist unser Gott Roussel – Joueurs de flûte Schumann – Lieder und Gesänge volume I (5 songs) Shostakovich – The Bolt Sibelius – King Christian II (), theatre score and suite (1898, revised and arranged 1898) Spohr – String Quartet No. 6 Strauss – Cäcilie Strauss – Morgen! Strauss – Ruhe, meine Seele! Suk – Asrael Symphony Szymanowski – Symphony No. 3 Waterhouse – Cello Concerto Webern – Variations for piano Wirén – Symphony No. 4 (1952) Ysaÿe – Six Sonatas for solo violin Violin Sonata No. 2