ATU

Atu may refer to:
 * Atu, a character in Samoan mythology
 * Atu Bosenavulagi, an Australian rules footballer
 * Atu, Iran, a village in Iran
 * Atu Moli, New Zealand rugby union player
 * Atu'u, a village on Tutuila Island, American Samoa

ATU may refer to:

Organizations

 * African Telecommunications Union
 * Allameh Tabataba'i University, Iran
 * Amalgamated Transit Union, trade union in Canada and USA
 * Arkansas Tech University, United States
 * Atlantic Technological University, Ireland
 * ATU Network was a caucus group within the Amicus trade union
 * Autoridad de Transporte Urbano
 * Anti-Terrorist Unit (Liberia)
 * Lučko Anti-Terrorist Unit, Croatia
 * Asian Taekwondo Union, the official governing body for Taekwondo in Asia

Other uses

 * Aarne–Thompson–Uther classification, a catalogue of folktale types
 * Abstract Tribe Unique, rap musicians using #ATU hashtag
 * Accumulated thermal unit
 * Address translation unit
 * Antenna tuning unit
 * Finnish Rapid Deployment Force
 * Antenatal testing unit
 * Assessment and treatment unit
 * Autonomous territorial unit, a type of administrative division in Moldova