Xu or XU may refer to:
Science and technology:
X unit (symbol xu), a unit of length approximately equal to 0.1 pm (10−13 m), used for X-ray and gamma ray wavelengths
PSA XU engine, a series of petrol engines from PSA
Universities:
Xavier University in Cincinnati, United States
Xavier University of Louisiana, United States
Xiamen University, Xiamen, Fujian, China
Xinjiang University, Ürümqi, Xinjiang, China
Other uses:
Xu (currency), a former 1/100 subdivision of the Vietnamese Dong
Xu (state) (徐), a state during the Zhou Dynasty of ancient China
Xu (surname), one of two Chinese surnames (徐 or 许/許), transliterated as Xu in English
ǃXu, a name for the ǃKung group of Bushmen; may also refer to the ǃKung language or the ǃKung people
ǃXu (god), the creator god of the ǃKung
Xu, a minor character in the game Final Fantasy VIII
XU (intelligence organisation), a clandestine intelligence organisation in occupied Norway during World War II