This article analyzes the M community action process through the fight against coronavirus pneumonia, and discusses the mechanism of community action. The research finds that the relationship between the individual interests of community members and the overall interests of the community is the fundamental driving force that promotes community action generation, and it is manifested through community problems, organizers of community action and community traditions. Based on the mechanism of M community's against coronavirus pneumonia, three suggestions for community construction are put forward: to cultivate the ability of community managers, to cultivate volunteers and to cultivate community culture.