| OPPA | Ontario Provincial Police Association (Canada) | 安大略省警察协会（加拿大） |
| OPPA | Oregon Public Purchasing Association | 俄勒冈州公共采购协会 |
| OPPA | Ohio Promotional Products Association | 俄亥俄州促销产品协会 |
| OPPA | Ontario Political Payoff Act | 安大略省政治收益法 |
| OPPA | dioctylpyrophosphoric acid | 二辛基焦磷酸 |
| OPPA | Office of Policy, Planning and Analysis | 政策、规划和分析办公室 |
| OPPA | Operation Plan Package Appraisal | 作战计划一揽子估价 |