It is said that cerebral angiospasm affects very seriously the prognosis of the patient with ruptured aneurysm. Of 44 patients with ruptured aneurysm who died from cerebral ischemia due to cerebral angiospasm, we performed histopathological studies of brains of 18 patients without iatrogenic factors (radical surgical operation, prolonged artificial breathing and so on). In all of the cases, cerebral infarctions were observed in the area fed by the artery with angiospasm. The size and extent of the cerebral infarction were various. In 12 cases who died in the acute stage (within 3 weeks after subarachnoid hemorrhage), those who survived longer showed more severe and wide cerebral infarction, while those who died earlier showed more localized infarction in the basal ganglia and thalamus. In 6 cases who died in the chronic stage (more than 3 weeks after subarachnoid hemorrhage), the cerebral infarction was slight. No ischemic changes were observed in the brain stem, except for secondary petechial hemorrhage due to incisural herniation in cases with extensive cerebral infarction.