In music, Op. 73 stands for Opus number 73. Compositions that are assigned this number include:

Beethoven – Piano Concerto No. 5 Brahms – Symphony No. 2 Czerny – Variations on "Gott erhalte Franz den Kaiser" Draeseke – Tod und Sieg des Herrn Krenek – Karl V Novák – May Symphony Schumann – Fantasiestücke, Op. 73 Shostakovich – String Quartet No. 3 Sibelius – The Oceanides (), tone poem for orchestra (1914, revised 1914) Strauss – Frohsinns-Spenden Weber – Clarinet Concerto No. 1