The paper surveys the historical development process of the principle of “being in need and volunteering” in social education, focuses on the educational organization form and educational content, and analyzes the practical effect of the principle from both positive and negative sides. It shows that implementation of the principle of “being in need and volunteering” is one of the key reasons for the success of social education. In the current crucial period of further reform in difficult areas, it is necessary to carry on implementing and developing the principle of “being in need and volunteering”, in order to effectively launch masses education campaign and mobilize the masses to accomplish the historical mission.