Because of the evolution of community supported collaborative learning (CSCL), the online community has become a necessary aspect of most companies and organizations. Previous research has indicated that employee community commitment is the fundamental function of an organization, which has proven to affect a person's teamwork performance. However, research focused on how the online community-supported collaborative virtual environment, such as enterprise social network (e.g., Yammer) or virtual working space (e.g., SUN's Wonderland) might alter community commitment to affect a person's teamwork self-efficacy is scant. We examine the mediating role of community commitment with emotional social support as an independent variable and teamwork performance as an output variable. World of Warcraft (WOW), a dynamic high-fidelity virtual environment that can support hundreds to thousands of people collaborating together, serves as the research platform in this study. We conducted hierarchical regression analysis to explore the causal-effect relationship among the factors of emotional social support, community commitment, and teamwork self-efficacy. In total, 558 current company employees selected from WOW participated in an online survey. Our findings showed that individual commitment positively influences teamwork self-efficacy. To increase individual commitment, the online community can provide a high level of emotional social support to members.