Major categorical diagnosis by International Classification of Diseases and type-specific diagnosis for cardiovascular diseases in death certificates were compared to the diagnosis made at autopsy in 864 consecutive autopsy cases aged 20 or over, among the Japanese residents in Hisayama town. Cerebral stroke was correctly diagnosed in 84%, malignant neoplasms in 78% and cardiac disease in 66%. Cerebral stroke and cardiac disease tended to be overdiagnosed, while malignant neoplasms were underdiagnosed. The validation of certified diagnosis was less reliable in the aged population, and in type-specific diagnosis of cardiovascular diseases. Cerebral hemorrhage with false negative or false positive diagnoses was usually classified into type unspecified stroke or different categories of cerebral stroke, while those misdiagnosed as cases of cerebral infarction frequently had no significant lesions in the autopsied brain. Finally, the relationship between the validation of diagnosis on the death certificates and the secular trend in cardiovascular disease in the Japanese vital statistics was discussed.