This study investigated the relation between positive and negative experiences of social support and mortality in a population-based sample. Data were derived from Dutch men and women aged 20–59 years who participated in the Doetinchem Cohort Study in 1987–1991. Social support was measured at baseline and after 5 years of follow-up by using the Social Experiences Checklist indicating positive ( n = 11,163) and negative ( n = 11,161) experiences of support. Mortality data were obtained from 1987 until 2008. Cox proportional hazards regression models, adjusted for age and sex, showed that low positive experiences of support at baseline were associated with an increased mortality risk after, on average, 19 years of follow-up (hazard ratio = 1.26, 95% confidence interval: 1.04, 1.52). Even after additional adjustment for socioeconomic factors, lifestyle factors, and indicators of health status, the increased mortality risk remained statistically significant (hazard ratio = 1.23, 95% confidence interval: 1.01, 1.49). For participants with repeated measurements of social support at 5-year intervals, a stable low level of positive experiences of social support was associated with a stronger increase in age- and sex-adjusted mortality risk (hazard ratio = 1.57, 95% confidence interval: 1.03, 2.39). Negative experiences of social support were not related to mortality.