With the development of new communication technologies,the boundary between public sphere and private life has been consistently blurred. A considerable number of virtual communities appear in every corner of the Internet.Among them, online fan communities have become one of the most active online social groups.Where does group solidarity come from?What kind of role do technologies play in online fan communities?This paper examines these questions from the aspect of interaction ritual chain theory. By conducting participant observation and ethnography in the online fan community of “theManWhoCameFromtheStar,”this study finds that online live broadcasting is an important ritual that maintains group dynamics,and the real-time discussion is the foundation of the formation ofthe community’s shared focus and mood.