Infraoptic course of anterior cerebral artery (ACA) is a rare cerebral vascular anomaly frequently associated with intracranial aneurysm. A 58-year-old woman suffered, subarachnoid hemorrhage due to aneurysmal rupture. Carotid angiography revealed multiple aneurysms and bilateral infraoptic course of ACA. Usual A1 segments were not visualized on both sides. These findings were also confirmed by craniotomy. Only 46 cases have been reported including ours. In this paper, we reviewed previously reported cases and the cause of aneurysm formation was discussed.