Online gaming has become a common form of leisure and entertainment, and office workers are a key target group. Studies have revealed that interpersonal relationships are a strong motivation for office workers to participate in online gaming, but few studies have analyzed how online gaming, which was originally entertainment oriented, has transformed into a tool for office workers to manage their interpersonal relationships. This study explored theories of online gaming, the notion the third place, and how office workers use the social capital of online gaming in both virtual spaces and reality from an ethnographic perspective. In addition, this study analyzed the correlation between players’ online, offline and social capital. Finally, this study proposed that online gaming has both positive and negative effects on the social capital of enterprises and individuals. When used effectively, online gaming can help office workers convert social capital and create opportunities for cooperation. However, differences among players’ understanding and evaluation of online gaming may lead to conflict, reduce group trust, and cause the loss of social capital.