This paper discusses whether the enterprise social capital which represents a broader corporate social relation can ease financing constraints of the small and medium-sized enterprise, and its internal mechanism. In samples of Chinese small and medium-sized listed companies, we found that enterprise social capital can effectively alleviate the financing constraints through the information effect and resource effect. The information effect and resources effect of corporate social capital alleviate financing constraints of small and medium-sized enterprises respectively by reducing the information asymmetry of enterprises and the money supplier and strengthening the acquisition of resources. By comparison, resource effect plays a more important role.