A case of tumor to be diagnosed as pleomorphic xanthoastrocytoma (Kepes) is reported. This patient was a 34-year-old female with a 6-year history of TIA. Neurological examination on admission showed no abnormalities except for bilateral choked disc. Plain CT scan revealed a well-defined low density area with a small high density region in the right temporal lobe. The small high density region and a part of peripheral portion of low density area were moderately enhanced with contrast media. At operation there was a cyst containing xanthochromic fluid at 1.5 cm depth from the cerebral surface. Temporal lobectomy and subtotal removal of tumor (5gr) were performed. The patient received postoperative radiation therapy (5960 rad). She has been doing extremely well for these 5 years following craniotomy and has no deficits except for the left upper quadrant hemianopsia which appeared immediately after surgery. There cannot be observed any symptoms or signs suggesting tumor recurrence. Histologically the tumor cells displayed marked pleomorphism. However, either necrosis or mitosis were very hard to find. The tumor cells were surrounded by a dense network of reticulin fibers. Electron-microscopically the tumor cells were occasionally filled with glial fibrils, and lipid granules were seen. Immunoperoxidase technique revealed both glial fibrillary acidic protein (GFAP) and S-100 protein in the cytoplasm of tumor cells, suggesting of neuroectodermal origin. Although this patient is older than previously reported cases (age 3 to 32), the histological findings as well as the good postoperative course indicate that this case may fulfill the criteria of pleomorphic xanthoastrocytoma first proposed by Kepes et al.