XY may refer to:
In science:
- coordinates, a system used to locate a point in two dimensions according to the cartesian coordinate system
- XY sex-determination system, a system in biology
- XY model, a model in physics
In spelling:
- Xy (digraph), a digraph of the Romanized Popular Alphabet, used to write Hmong
In culture:
- X&Y, an album by Coldplay
- XY (magazine), a gay male youth magazine that also operated a personals website
- Xy (formerly known as Xytras), a member of the band Samael
In other uses:
- Kyle XY, a television show broadcast by the American Broadcasting Company
- Aktenzeichen XY … ungelöst, television programme broadcast (ZDF)