Virtual community provides people increased opportunities to interact and form bonds with others. From the company perspective, it can broaden the scope and reach of customer relationships. Hence, scholars have been interested in people’s interactions in virtual community and their related outcomes. Knowledge sharing, a positive helping behavior, is commonly regarded as essential for both virtual community and their participants. And it has become evident that it is the basis of virtual community. As a result, increasing research interests have been raised by western scholars in this area. Knowledge sharing has been studied from various perspectives, the most promising one of which is sense of virtual community (SOVC). Addressing numerous calls for future research on understanding the theoretical mechanisms that explain the relationship between sense of virtual community (SOVC, including SOVCM, SOVCIN and SOVCIM ) and intention of sharing knowledge, this study focused on how an member’s virtual community organizational citizenship behavior (VC-OCB) mediate the relationship his/her sense of virtual community and his/her intention of sharing knowledge. It also looked at how self-efficacy might moderate this mediated relationship. To avoid the common method bias, a paired survey for virtual community participants and their friends was used. Questionnaire A included scales of sense of virtual community, self-efficacy, intention of sharing knowledge and virtual community organizational citizenship behavior was appraised on Questionnaire B. The survey was distributed via applied psychology students. Hierarchical Regression Modeling (HRM) and Total Effect Moderation Model with bootstrap methods were used to test the hypotheses. The results of an empirical study involving 445 virtual community members indicated that SOVCM had significantly positive impact on the intention of sharing knowledge. In addition, the results of mediating test showed that, virtual community organizational citizenship behavior acted as a mediator between the relationship of SOVCM and intention of sharing knowledge. Finally, results of total effect moderation model analysis suggested that self-efficacy didn’t significantly moderate any paths of this mediated relationship. Our findings contribute to the literature in several ways. First, this research offers a new perspective to study the mediating mechanisms underlie the relationship between SOVCM and intention of sharing knowledge in virtual community. Second, our research divided SOVC into three parts and suggested that every part had different impact on the intention of sharing knowledge. More importantly, the integration of the mediating and moderating models provide a more comprehensive and elaborative interpretation of the linkage between SOVC and intention of sharing knowledge.