The C.T. findings of 33 intracerebral hematomas are described. During the first week intracerebral hematomas were visible as a sharply demarcated lesion with markedly increased density without contrast enhancement. Thereafter the density decreased gradually and after 30 days the density was always lower than that of cerebral tissue. Depending on the etiology of the hemorrhage, differences were found in the localization, shape and density of the lesion on the C.T. scan. Secondary mass effects could be evaluated precisely. On first interpretation, 94% of the hematomas were recognized as focal lesions (2 false negative) and 85% as intracerebral hematomas (2 false negative and 3 incorrect). False positives were absent. The review C.T. diagnosis was correct in 94%. In the diagnosis of intracerebral hematomas, C.T. was found to be superior to all other investigations both quantitatively and qualitatively. C.T. also has therapeutic consequences since the operability can be much better judged than before.