| OSI | Open Source Initiative | 开源组织 |
| OSI | Open System Interconnection | 开放系统互连 |
| OSI | Open Society Institute | 开放社会协会 |
| OSI | Congregatio Oblatorum Sancti Ioseph (religious order, Oblates of St. Joseph) | Oblatorum Sancti Ioseph公理会（宗教秩序，圣约瑟夫州） |
| OSI | Office of Scientific Information | 科学情报处 |
| OSI | Optical Storage International | 国际光存储 |
| OSI | Open Standard Interconnection | 开放标准互连 |
| OSI | Oponix Systems Inc. | Oponix系统公司。 |
| OSI | Origin Systems Incorporated | Origin Systems公司 |
| OSI | Office of Scientific Intelligence | 科学情报处 |
| OSI | Operator System Interface | 操作员系统界面 |
| OSI | Ontario Swine Improvement Inc. (Ontario, Canada) | 安大略猪改良公司（加拿大安大略省） |
| OSI | Open Systems Interconnection | 开放系统互连 |
| OSI | Open Systems, Inc. | 开放系统公司。 |
| OSI | Office of Special Investigations | 特别调查处 |
| OSI | Open System Interface | 开放系统接口 |
| OSI | Open Systems Interoperability | 开放系统互操作性 |
| OSI | On-Site Inspection | 巡检 |
| OSI | Ounces per Square Inch | 盎司\/平方英寸 |
| OSI | Other Similar Incidents | 其他类似事件 |
| OSI | Operating System Intelligence | 操作系统智能 |
| OSI | Other Security Interests | 其他担保权益 |
| OSI | Orchestra Of Strategic Influence | 战略影响力乐团 |
| OSI | Operational Support Inventory | 运营支持库存 |
| OSI | Only Suckers Initialize | 仅吸盘初始化 |
| OSI | Outsourcing Solutions Inc. | 外包解决方案公司。 |
| OSI | Office of Strategic Information | 战略情报处 |
| OSI | Origin Systems, Inc. | Origin Systems公司。 |
| OSI | Open Source Institute | 开源研究所 |
| OSI | Organizational Strategies, Inc. (Arlington, VA) | 组织战略公司（弗吉尼亚州阿灵顿） |
| OSI | Office Of Strategic Intelligence | 战略情报办公室 |
| OSI | Office Of Special Investigation | 特别调查办公室 |
| OSI | Officine Stampaggi Industriale | 官方Stampaggi Industriale |
| OSI | Optimal System Integration | 最佳系统集成 |
| OSI | Office of Secret Intelligence (fictional, Venture Brothers) | 秘密情报办公室（虚构，Venture Brothers） |
| OSI | Office of Strategic Initiatives | 战略倡议办公室 |
| OSI | Other Supplemental Information | 其他补充信息 |
| OSI | Online Software | 在线软件 |
| OSI | Office of School Improvement | 学校改善办公室 |
| OSI | Offshore Systems, Inc | 海上系统公司 |
| OSI | Office of Strategic Influence (band) | 战略影响力办公室（乐队） |
| OSI | Osram Sylvania Inc. | Osram Sylvania公司。 |
| OSI | Open Switching Interval | 打开切换间隔 |
| OSI | Optimum Source Impedance | 最佳源阻抗 |
| OSI | Originating Station Identifier | 始发站标识符 |
| OSI | Office of Statewide Intelligence (FDLE) | 全州情报办公室（FDLE） |
| OSI | Office of Science and Innovation | 科学与创新办公室 |
| OSI | One Side Installation | 单面安装 |
| OSI | operational subsystem interface (US DoD) | 作战子系统接口（美国国防部） |
| OSI | Open System Integration | 开放系统集成 |
| OSI | Out of Stock Indefinitely (usually referring to books) | 无限期缺货（通常指书籍） |
| OSI | Operations System Interface | 操作系统界面 |
| OSI | Operating Space Item | 实施中的空间项目 |