Few tools for risk assessment of coronary heart disease (CHD) have yet been made available in Japan. This study aims to examine the validity of the updated Framingham risk score as applied to a Japanese male population. Using the annual health examination database of a Japanese company, we followed-up 5,611 male subjects, aged 30 to 59 years, who had initially recorded neither history of cardiovascular disease nor electrocardiographical ischemic changes, in order to observe the occurrence of CHD over a period of 5 to 7 years. The total score calculated by the Framingham risk score sheet (the Framingham point score) was used as an indicator of CHD risk for the subject individually. The mean of the Framingham point score for 80 CHD cases was significantly higher than that for 5,531 non-CHD cases. The incidence of CHD gradually increased with the Framingham point score. In the receiver operating characteristic analysis, the area under the curve reached 0.71. At 6 points, the curve came closest to the upper left-hand corner, with a specificity of 0.74 and sensitivity of 0.59. On the other hand, multivariable-adjusted relative risks associated with old age, high blood pressure, low HDL cholesterol and smoking in the Japanese male population were different from those in the Framingham population. Despite the low incidence of CHD, the updated Framingham risk score could provide a reasonable rank ordering of CHD risk and could identify Japanese men (and possible other individuals) at high risk for CHD with considerable accuracy. However, further study of Japanese populations may be required to reappraise several coefficients of risk factor in the risk scoring model.