AAB may stand for:

• Aalborg Boldspilklub
• ABN AMRO Bank
• 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)