Computerized tomography (CT) scans of 450 standardized normal persons from 5000 consecutive patients were examined to study the relationship between the incidence of intracranial calcification and aging process. The 450 subjects were classified into 9 groups according to age. In people older than 30 years, calcification in the pineal region including pineal body and habenular commissure was found in about 70%. Calcified choroid plexus seems to be characteristic of aging process because the rate of its calcification increased in proportion to aging. Calcification of the falx cerebri was also found to increase in proportion to aging. Calcified cerebral arteries were observed in advanced-aged groups. The fact that people in the ninth decade had a smaller incidence in calcification of the cerebral artery than those in the eighth decade indicates the possibility that longer-lived people had less incidence of cerebral arterial calcification.