a b s t r a c tWe examined the relationship between social capital, coplaying patterns and health disruptions in a large sample of gamers in a popular Chinese Massively Multiplayer Online Game, Chevaliers' Romance 3. Partnering with the game operator, we fielded an online survey (N = 18813) in 2011. Social capital was measured by (1) psychometric measures of bridging and bonding social capital, and (2) core discussion network size using name generators, as well as the number of strong and weak ties within the core network. Controlling for sociodemographic variables, we found that bonding social capital was associated with lower odds of frequent or occasional health disruptions, but bridging social capital did not have any effect. Weak ties in the core network were associated with greater odds of health disruptions. Coplaying patterns also mattered -people playing with friends first met through CR3 were less likely to have health disruptions, while playing with existing friends and families tended to have the opposite effect.Overall, social capital and coplaying patterns appear to have significant health implications for participants in online games.