ADU or Adu may refer to:
Aviation
- IATA airport code for Ardabil Airport in Ardabil Province, Iran
Universities
- Abu Dhabi University
- Adamson University of Manila
- Afghan Defense University, now called Marshal Fahim National Defense University
- Animal Demography Unit, University of Cape Town
- ArsDigita University at MIT
Other uses
- Accessory dwelling unit or secondary suite
- Adu (surname)
- Adú, 2020 Spanish film
- Ammonium diuranate
- Analog-to-digital converter or Analog-to-digital unit
- Application discovery and understanding
- Ädu, village in Otepää Parish, Valga County, Estonia