Under the analytical framework of new institutionalism, legitimacy has a decisive influence on the survival practice of organizations. However, social enterprises are still a relatively new thing in China, and their legitimacy has a certain ambiguity. Studying the legal acquisition path of social enterprises under the current institutional environment in China can effectively promote the standardized development of social enterprises. Articles equipped with "consciousness - entrepreneurship and mission to build - robustness development" characteristics of the local social enterprises typical case, the classical theory of political organization promotion to social enterprise research category, analysis and organization legitimacy fuzzy system under legitimacy can assign a top-down social legitimacy building enterprise strategy and the theory explanation. The findings: Through the function of organizing flexible and practical effectiveness to win major related group of its organizational behavior identity, generated and accumulated organizational behavior legitimacy, which in the system environment has provided the safeguard for the organization’s survival and development, which can be summed up as gain legitimacy and effectiveness in the model for the development of Chinese social enterprises localization is of high reference value. This paper also expands the reunderstanding of the connotation of validity under the model of cumulative validity. This paper is helpful to enhance the understanding of the development path of local social enterprises at the present stage and provide a cutting-edge model for social entrepreneurs.