非政府组织（英语：Non-Governmental Organization，缩写：NGO）是一类不属于任何政府、不由任何国家创建的组织，不属于政府的机构,通常独立于国家政府。虽然从定义上包含以营利为目的的企业，但该名词一般仅限于非商业化、合法的、与社会文化和环境相关的倡导群体。非政府组织通常是非营利组织，他们的基金至少有一部分来源于私人捐款。现在该名词的使用一般与联合国或由联合国指派的权威非政府组织相关。

由于各国文化、法律等的差异，不同国家对这个概念的指称所适用的对象范围也各不相同。美国一般称之为“非营利组织”、“独立组织”或“第三部门”（The Third Sector），英国称之为“志愿组织”（voluntary organization），还有许多国家则用“社团”称之。

A non-governmental organization (NGO) is an organization that is neither a part of a government nor a conventional for-profit business.

Usually set up by ordinary citizens, NGOs may be funded by governments, foundations, schools, businesses, or private people. Some avoid formal funding altogether and are run primarily by volunteers. NGOs are highly diverse groups of organizations engaged in a wide range of activities, and take different forms in different parts of the world. Some may have charitable status, while others may be registered for tax exemption based on recognition of social purposes. Others may be fronts for political, religious, or other interests.