Lifetime risk is an informative estimate to motivate people to change lifestyle behaviors, especially from a younger age, in public health education. The impact of the combination of hypertension and diabetes on the lifetime risk of cardiovascular mortality has not been investigated in Asian populations. A pooled analysis of individual data from nine cohorts was performed. A total of 57,339 Japanese men and women were eligible for the analysis. We used the modified Kaplan-Meier approach and estimated the remaining lifetime risk of cardiovascular mortality starting from the index age of 35 years. Participants were classified into four categories defined by hypertension and diabetes. The lifetime risk was increased in the order of those without either risk, those without hypertension but with diabetes, those with hypertension but without diabetes, and those with both risks. The lifetime risk of cardiovascular mortality at the 35-year index age was as follows: 7.8% in men and 6.2% in women for those without either hypertension or diabetes, 13.2% in men and 9.5% in women for those without hypertension but with diabetes, 17.2% in men and 11.7% in women for those with hypertension but without diabetes, and 19.4% in men and 15% in women for those with both risks. These findings reinforce the need for a life-course perspective in the management of hypertension and diabetes from a younger age.