Social media continues to serve as vehicles for fostering relationships with customers. One specific way to implement this is to create and operate brand fan communities on social networking sites. Brands can place posts (including videos, messages, quizzes, information, and other material) in these brand communities. By customer’s reposting or commenting on the posts, it subsequently reflects the brand post popularity. In order to investigate the possible drivers for brand post popularity in the Chinese social media context, this thesis selects Tuborg’s Green Fest as the case, its official account on Weibo as the platform, and analyzes the correlation between six driven factors and brand post popularity pairwise.  Results show that interactivity is the most important factor for popularity; a higher level of interactivity would help boost popularity. Followed by entertaining content and vividness are also two factors that positively related to brand post popularity. Moreover, the post theme of Fans interaction is most popular with fans, while the theme of Green Fest information would have negative impact on post popularity. Nevertheless, informational content is not welcome by the fans either, which may have a negative influence on popularity. Managers of brands that operate brand fan communities can be guided by this research with regards to deciding which characteristics or content to place in their brand posts.