Background The concept of social capital has received increasing attention as a determinant of population survival, but its significance is uncertain. We examined the importance of social capital on survival in a population study while focusing on gender differences. Methods We used data from a Danish regional health survey with a five-year follow-up period, 2007?2012 (n=9288, 53.5% men, 46.5% women). We investigated the association between social capital and all-cause mortality, performing separate analyses on a composite measure as well as four specific dimensions of social capital while controlling for covariates. Analyses were performed with Cox proportional hazard models by which hazard ratios and 95% confidence intervals were calculated. Results For women, higher levels of social capital were associated with lower all-cause mortality regardless of age, socioeconomic status, health, and health behaviour (HR=0.586, 95% CI=0.421-0.816) while no such association was found for men (HR=0.949, 95% CI=0.816-1.104). Analysing the specific dimensions of social capital, higher levels of trust and social network were significantly associated with lower all-cause mortality in women (HR=0.827, 95% CI=0.750-0.913 and HR=0.832, 95% CI=0.729-0.949, respectively). For men, strong social networks were associated with a higher risk of all-cause mortality (HR=1.132, 95% CI=1.017-1.260). Civic engagement had a similar effect for both men (HR=0.848, 95% CI=0.722-0.997) and women (HR=0.848, 95% CI=0.630-1.140). Conclusions We found differential effects of social capital in men compared to women. The predictive effects on all-cause mortality of four specific dimensions of social capital varied. Gender stratified analysis and the use of multiple indicators to measure social capital are thus warranted in future research.