Social media sites like Facebook have recently been blamed for their negative impact on wellbeing, with support from recent research. However, certain features and mechanisms of social media sites may actually increase their users’ wellbeing, and the sites may serve as platforms for positive interventions to reach large populations and improve their lives. This paper examines China’s leading Social Network, WeChat, and its potential effectiveness in cultivating wellbeing among Chinese users, through a review of the literature. The paper has six sections. Part 1 presents a brief summary of Positive Psychology and Positive Interventions. Part 2 reviews research findings regarding the impact of social media on wellbeing. Part 3 introduces WeChat’s design features and how they may affect the users’ behaviors. Part 4 suggests six hypotheses on how WeChat may improve user wellbeing. Part 5 proposes possible ways to apply positive interventions on WeChat which would enable users to actively improve their wellbeing. Finally, Part 6 reviews how datasets from various social networks have assisted psychological and developmental research. The last section also outlines a quantitative research proposal to validate the hypothesis that WeChat makes a positive impact on users’ wellbeing, and offers limitations and implications for future work.