ABU is a three-letter acronym that may refer to:

  • Airman Battle Uniform, a new utility uniform for the U.S. Air Force.
  • Asia-Pacific Broadcasting Union
  • Atlantic Baptist University, a Christian university located in Moncton, New Brunswick, Canada
  • l'Association des Bibliophiles Universels, a digital library project that publishes French works in the public domain
  • Haliwen Airport (IATA airport code: ABU) in Atambua, Indonesia
  • Ahmadu Bello University, a university located in Zaria, Nigeria.
  • ABU Garcia, a Swedish producer of sportfishing equipment
  • Asymptomatic bacteriuria, bacteria in the urine without signs of a urinary tract infection
  • Anyone But United, a phrase referencing how many football fans would rather see any other club besides Manchester United succeed.