A case of renal schwannoma is presented. A 51-year-old female was admitted to our hospital because of a left renal mass on April, 16, 1987. A drip infusion pyelogram showed encasement of the lower and medial calyx. An abdominal CT-scan showed a 2.5 cm mass with irregular density. Selective left renal arteriography showed the hypovascular tumor of the left kidney. Transperitoneal radical nephrectomy was performed on May, 1, 1987. Histological diagnosis was renal schwannoma arising from renal pelvis. The patient was well without recurrence 20 months after operation. Our present case is the 12th case of renal schwannoma reported in the English and Japanese literature.