CT has been established as a useful imaging method in the diagnosis of tuberous sclerosis. By demonstratingthe characteristic intracranial lesion, it allows confirmation of the diagnosis and provided a noninvasive meansof evaluating the patient with seizure and mental retardation. Authors analysed CT findings in 20 cases oftuberous sclerosis since March 1985 through August 1988. The results were as follows: 1) There are 14 men and 6women with the age raging from 6 months to 45 years. 2) Ventricular calcified tubers are noted at the frontal horn(16/20,80%) body (13/20, 65%), atrium (9/20,45%) of the lateral ventircles, 1 case shows the hamartoma near theforamen of Monro. 3) In the cortical region , 1 case of high density tuber and 2 cases of focal atrophy are noted.4) In the white mater, 3 cases of amorphous calcifications and 1 case of demyelinating hypodensity are seen.