To examine whether the risk of mortality varies according to parents' age at death. A large prospective study in Japanese men and women from 45 communities across Japan. A total of 51 485 men and women aged 40-79 years completed self-administered questionnaires at baseline and followed up for 9.6 years. The risk of mortality from stroke, cardiovascular disease, and all causes was 20-30% lower in men and women with fathers who died at age > or = 80 years, compared with those with fathers whose age at death was <60 years. A similar reduction was found when the age at death of mothers was > or = 85 years compared with <65 years. Furthermore, the risk reduction was more evident amongst persons with both parents being long-lived parents compared with those with being short-lived parents, especially for death from cardiovascular disease. Our findings indicate that parental longevity could be a predictor for reduced risk of mortality from stroke, cardiovascular disease, and all causes for both Japanese men and women.