Radiologic findin g of rena l oncocytoma is characte ri stic; The tumor is relatively well circumscribed , homogeneous, and solid mass with central ste ll ate fibrotic scar on CT and ultrasonog raphy, and hypervascular mass w ith spoke-whee or pineapple-co re appearance on angiography We repo rt a case of rena l oncocytoma proven by th e electron microscopic findings with rev iew of the literatures