Op. 18
# Op. 18

In music, Op. 18 stands for Opus number 18. Compositions that are assigned this number include:

* Balakirev – Islamey
* Beethoven – String Quartets Nos. 1–6, Op. 18
* Berlioz – Tristia
* Brahms – String Sextet No. 1
* Britten – Les Illuminations
* Chopin – Grande valse brillante in E-flat major
* Finzi – Let Us Garlands Bring
* Mendelssohn – String Quintet No. 1
* Nielsen – Søvnen
* Oswald – Piano Quintet
* Rachmaninoff – Piano Concerto No. 2
* Ries – Violin Sonata No. 9
* Schoenberg – Die glückliche Hand
* Schumann – Arabeske
* Strauss – Violin Sonata
* Tchaikovsky – The Tempest
* Zdeněk – The Bride of Messina
* Zemlinsky – Lyric Symphony
