Social enterprises are an innovative kind of social organization that have appeared all over the world in recent years. Different from government，enterprises and even NPOs in the common sense，they have attracted a great deal of attention and controversy. By combing through the main academic research and perspectives on social enterprises both in China and abroad，we summarize a framework for understanding social enterprises. The framework has two dimensions：the social enterprise phenomenon and social enterprises’ characteristics. We also have three angles—public-interest，market and cultural angles—from which to observe them. And we analyze them on four levels：market practices，public-interest innovations，policy support，and idealized values. Upon these foundations，social enterprises can be defined as a form of enterprise somewhere between public-interest and for-profit enterprises，a product of the organic combination of the public interest and the market economy，and a kind of social organization combining properties and characteristics of NPOs and enterprises. Their appearance and development have unfolded against a specific historical background. And while social enterprises in China have developed their own characteristics and specific models，there remain certain problems as well. Incorporating experiences and foundations from abroad，policy frameworks should be put in place to promote the development of social enterprises in China.