ARB is a TLA that may stand for:
- Accident Report Book (UK)
- Adaptive rate-based (congestion control)
- Africa Research Bulletin
- Air Reserve base
- Air Resources Board (California)
- American Research Bureau
- Angiotension receptor blocker (medicine)
- Appraisal review board
- Architects Registration Board (UK)
- Architecture Review Board (OpenGL and others)
- Armee Revolutionnaire Bretonne
- Armored rifle battalion
- Army Resources Board (US)
- Assessment review board (several)
- Asset Recovery Business (Dell)
- SIL code for the Akawaio language of Guyana
- hull classification symbol for US Navy battle damage repair ships
- stock symbol for Arbitron Inc.
- abbreviation for arbitration