Twenty-nine patients with renal cysts were treated with sono guided percutaneous aspiration and injection of sclerosing agent. Three months to five years follow up. 11 of 29 cases have recurrence, but the size of cysts all were smaller than those of pre-management, and 9 of 11 cases were less than its original half size. There was no need for reaspiration of these recurrent cases under clinical symptoms and image study. No serious compIication was happended.