Living in a community with high social capital might lead to lower stigma towards people with mental illness. We examined the association between social capital and stigma toward people with mental illness in the community of Tokyo, Japan. A random sample of 2,000 community residents was selected and surveyed. Data from 516 respondents were analyzed. In this study, two individual-based social capital variables were significantly and negatively associated with the stigma score, while area-based social capital was not significantly associated with the stigma score. Social capital, particularly reciprocity/norm of cooperation and trust in the community, may be associated with lower stigma. © 2013 Springer Science+Business Media New York.