A cardiovascular epidemiologic survey has been carried out in three different areas (Sakuto-cho, Sanyo-cho and Osafune-cho) of Okayama Prefecture since 1966. Cerebro-cardiovascular risk factors were investigated using data obtained in the first examination. The following results were obtained: 1. Sixty-six cerebro-cardiovascular accidents (CCA) occurred in 1906 subjects over a ten year period (1966 to 1976); of these, 33 were cerebrovascular accidents (CVA) and 33 were cardiac accidents. The prevalence rate was the highest in Sakuto-cho and the lowest in Sanyo-cho. This reflected the degree of control of blood pressure. 2. Cardiovascular accidents had a slightly higher prevalence rate in females than in males. 3. CCA in males showed a positive correlation to increase in relative body weight. In females, there was no significant relationship between CCA and relative body weight. 4. Compared to subjects with normal urinalysis, the prevalence rate of CCA was 1.7 in subjects with proteinuria and 3.2 in those with glucosuria. 5. CCA occurred more frequently in both the systolic hypertension group and the group with combined systolic and diastolic hypertension.