Fifteen cases of surgically proved isodense sugdural hematoma on CT were studied in the Hanyang University Hospital from Feb. 1979 Aug. 1981. The medical records and CT films were reviewed. The results were as follows : 1. The age distribution is broad from 12 years to 73 years old. The peak age incidence is in the 6th decade, The most of the cases were male. 2. 12 out of 15 cases were conscious at the time of CT examination, and the rest of them were stuporous or unconscious. 3. 10 out of 15 cases had history of head injury, In 6 cases the intervals between head injury and CT examination were more than 3 weeks. 5. Skull radiograms showed a fracture in the right frontal bone in 1 cases. 5. In computed tomgrams shifting of mid-line structures were observed in 14 out of 15 cases, compression and local deformities of the ipsilateral lateral ventricles in 14 cases, dilatations of the contralateral lateral ventricles in 14 cases, unilateral effacement of the cortical sulci in 14 c ses.