CT scans were analysed retrospectively in 130 patients with subarachnoid hemorrhage(SAH) due to ruptured cerebral aneurysm to evaluate the relationship of the locations of aneurysms and the patterns of hemorrhage. Hemorrhage corresponded to the site of aneurysmal origin in a general way and in more specific ways to anterior communicating and middle cerebral artery aneurysms when there was parenchymal or cisternal hemorrhage. In anterior communicating artery aneurysm, SAH in the interhemispheric fissure, both sylvian fissures, and basal cistern was usually noted and intracerebral hemorrhage in anteroinferior frontal lobe was sometimes associated. In cases of middle cerebral artery aneurysm, hemorrhage in the ipsilateral sylvian fissure, interhemispheric fissure, and ipsilateral basal cistern was usual. Intracerebral hemorrhage inlateraltemporal lobe was sometimes associated. posterior communicating artery aneurysm demonstrated SAH in the ipsilateral basal cistern or in entire c sternal spaces specifically, so with higher incidence of involvement of the quadrigeminal and superior cerebellar cistern than anterior cerebral or middle cerebral artery aneurysm. We suggest the locations of aneurysm might be predicted with patterns of SAH and/or associated intracerebral hemorrhage with CT.