Preoperative transarterial embolization procedures have been performed in 12 intracranial meningiomas, which were emobolized by superselection technique of the branches of the external carotid artery, using Berenstein superselective catheters or conventional angiographic catheters. PVA(polyvinyl alcohol) and/or Gelfoam particles were used as embolic material. Of the 12 patients, 9 cases were supplied from both internal and external circulation, and 4 of them showed profuse intraoperative bleeding, while 3 cases supplied only from the external circulation could be removed totally with little difficulty in bleeding control. The excised tumor specimens were examined for evidence of thrombosis and infarction, and 6 out of 12 cases showed evident tumor necrosis. Preoperative embolization of the meningioma produced relatively avascular operative conditions in most cases, but in those with dual blood supply, embolization may be of limited value due to an appreciable blood supply from the internal carotid artery.