Ganglion impar block is a known useful method of controlling perineal cancer pain. Moreover, this method may be suitable for hyperhidrosis because the visceral cancer pain signal and sweating are transmitted by the same sympathetic chain. We experienced a patients who had suffered from systemic hyperhidrosis especially in the sacral and buttock area. She also had long-standing diabetes mellitus and chronic renal failure. Her excessive sweating occurred during hemodialysis. We treated this patients using a ganglion impar block and achieved a good result.