'Vocalise' is a song by Sergei Rachmaninoff (1873-1943), composed and published in 1912 as the last of his 14 Songs or 14 Romances. Written for high voice (soprano or tenor) with piano accompaniment, it contains no words, but is sung using any one vowel of the singer's choosing. It was dedicated to soprano Antonina Nezhdanova.

Although the original publication stipulates that the song may be sung by either soprano or tenor voice, it is usually performed by a soprano. It is sometimes transposed into a variety of keys, allowing performers to choose a vocal range more suitable to their natural voice, so that artists who may not have the higher range of a soprano can perform the song.