ABSTRACT The prevalence of virtual brand communities and the knowledge sharing occurring throughout these populations has become a staple of both business and consumer online realities. Expanding work on personal motivations, and guided by self-determination theory, this research explores autonomous and relatedness motivations that drive individual knowledge sharing within online communities. The authors argue that such knowledge sharing can be fostered by many drivers, including self-presentation factors, brand community engagement elements, user attitude toward the brand, user reputation, size of community network, and reciprocity from other community members. Analysis was conducted using data collected longitudinally from 2866 club members of Xiaomi’s online MI User Interface community in China. Results reveal that personal signature, post length, online time, login frequency, brand attitude, reputation, online social network, and reciprocity all positively affect individual knowledge sharing within the virtual brand community, while the use of picture posts may have adverse effects and impact knowledge sharing negatively.