Abstract: Social organizations can gain the qualification to provide services in the community by undertaking the government purchase of public services. But they still need to take a series of action strategies to obtain recognition and acceptance from the community， and achieve the organizational development in this process. The study based on the theory of new institutionalism shows that， organization L synthetically uses the strategies of “complying with the environment”， “controlling the environment”， “choosing the environment” and “creating the environment” to get the recognition and support of the community participants. Meanwhile， social organizations need to establish “selectively coupling” between the requirements of legitimacy and efficiency in the process of “entering the community”. To avoid “over-coupling” or “decoupling”， the government should formulate policies in line with social expectations and professional norms， and social organizations should pay more attention to capacity-building so as to enhance their environmental adaptability.

Key words: social organization, community, legitimacy, selective coupling