We report the case of a 34-year-old woman who exhibited acute deterioration in her condition after cerebral angiography for evaluation of a large meningioma. She had undergone surgery and irradiation for a glioma in the right occipital lobe 23 years before this episode. She experienced incapacity at work. On CT and MRI, a large meningioma was detected on the left frontal convexity; this tumor was thought to be radiation-induced. Cerebral angiography was performed to assess the vascularization of the tumor. Her condition began to deteriorate 2.5 h after the cerebral angiography. CT revealed an increase in the mass of the tumor, and a high density area in the tumor. We immediately removed the tumor. Histopathological examination revealed the tumor to be a meningothelial meningioma. New hemorrhagic foci were identified in the tumor. In addition, macrophages containing hemosiderin were detected, and some of the tumor vessels exhibited hyaline degeneration. We suspected that angiography triggered bleeding in the meningioma, which was already predisposed to hemorrhage.