AAV or Aav may refer to:
- Allah Valley Airport (IATA airport code), in Allah Valley, Mindanao, Philippines
- Anti-aircraft vehicle, or self-propelled anti-aircraft weapon
- Amphibious Assault Vehicle, an amphibious tracked vehicle
- Adeno-associated virus, a harmless virus used as a gene therapy tool
- The NYSE ticker symbol for Advantage Oil & Gas Ltd., a Canadian oil and gas company
- Aníbal Acevedo Vilá, former governor of Puerto Rico (2005-2008)
- Air admittance valve, a valve in a drain-waste-vent system
- Arab American Vehicles, a car assembler in Egypt
- Evald Aav (1900–1939), Estonian composer