Music for an Aquatic Ballet is the most commonly used title to refer to an untitled composition by American avant-garde composer John Cage.

Even though the score of the composition is lost and has never been published nor performed after its premiere, some of Cage's fellow musicians have loosely reconstructed it.

However, the event was played and directed by John Cage himself, and the performance involved both synchronized swimming and live music.

However, it is commonly referred to as Music for an Aquatic Ballet, which is the description provided in Cage's book Silence: Lectures and Writings.

[2] Since the composition is lost and has not been mentioned many times in John Cage's papers, there is little information about instrumentation, duration and structure.