| OAB | Oman Arab Bank | 阿曼阿拉伯银行 |
| OAB | Ohio Association of Broadcasters | 俄亥俄广播协会 |
| OAB | Ostomy Association of Boston | 波士顿造口术协会 |
| OAB | Oregon Association of Broadcasters | 俄勒冈州广播协会 |
| OAB | Oklahoma Association of Broadcasters | 俄克拉荷马广播协会 |
| OAB | Ocean Affairs Board | 海洋事务委员会 |
| OAB | Over- Active Bladder | 膀胱过度活跃 |
| OAB | Operational Archives Branch (US Navy; Washington, DC) | 作战档案处（美国海军；华盛顿特区） |
| OAB | Ordem dos Advogados do Brasil (Brazilian Law Board) | Ordem dos Advogados do Brasil（巴西法律委员会） |
| OAB | Outlook Address Book (Microsoft) | Outlook通讯簿（Microsoft） |
| OAB | Oklahoma Accountancy Board | 俄克拉荷马州会计委员会 |
| OAB | Osan Air Base (Pyong-Taek City, Kyong-Gi Province, ROK) | 乌山空军基地（韩国庆吉省平泰市） |
| OAB | Over-Active Bladder (urology) | 膀胱过度活跃（泌尿外科） |
| OAB | Ordem dos Advogados do Brasil (Brazil) | Ordem dos Advogados do Brasil（巴西） |
| OAB | Operations Approval Board (USAF) | 作战批准委员会（USAF） |
| OAB | One Angry Boy | 一个愤怒的男孩 |
| OAB | Offline Address Book | 脱机通讯簿 |
| OAB | Official At Bat | 蝙蝠官方 |