Social change and development influence the motivational factors of people’s sports participation, exposing the need for socialization and interaction. The purpose of this study is to investigate the interaction pattern of the urban running community and the behavior pattern of runners with the help of social interaction theory, and to explore the inner connection between their community movement and social interaction. Ten senior members of marathon urban running societies were selected to conduct two rounds of in-depth interviews which were analyzed using qualitative thematic analysis to understand the sports participation experiences and social interactions of running society members. The study found that the whole interaction process of running groups is accomplished through three aspects: examination of self, adjustment with reference to others, and a sense of group belonging as the core consciousness. On the other hand, the social attributes of running groups can advance the personalization process of runners in society, which is mainly characterized by self-presentation and external constraints, self-requirement and group constraints, intergroup interaction and group identity reorganization. In addition, the unique community culture, standardized group organization and harmonious activity atmosphere will stimulate runners’ interest in running, strengthen community communication and establish stable community relations, etc., which in turn will bring about continuous interactive behaviors.