AAB may stand for:
- Aalborg Boldspilklub
- Aboriginal Affairs Branch (Canada)
- Agence Africaine de Biotechnologie (Algeria, aab.org.dz)
- Air Assault Badge
- Air assault brigade (UK)
- All-to-all broadcast
- American Association of Bahrain
- American Association of Bioanalysts (aab.org)
- American Association for Bioethics
- American Association for Bronchology
- Anti-aircraft battery
- Arbejdernes Andels Boligforening (Denmark, aab.dk)
- Arizona Aryan Brotherhood
- Army air base (USA)
- Association of Applied Biologists (UK, aab.org.uk)
- Asociación Andaluza de Bibliotecarios (Spain, aab.es)
- Associação dos Arquivistas Brasileiros (aab.org.br)
- Associazione Astrofili Bolognesi
- Augsburger Aktienbank (aab.de)