Objective To evaluate the clinical role of retroperitoneoscopic ureterolithotomy in the treatment of upper segment ureter stones.Method Retroperitoneoscopic ureterolithotomy was used to treat 18 patients,the diameter of stones ranged from 0.8 cm to 1.6 cm,the courses of disease were from 2 months to 1 years.The stones of all the patients were single,and 9 had undergone unsuccessful ESWL or ureteroscopy.Results All 18 cases succeeded uneventfully.The mean operation time was 75 min(60-120 min),and the estimated blood loss 10-50 ml.The postoperative hospital stay was 5-8 d with a mean of 6 d.There were no serious complications in the preoperative and postoperative period.During the 6-12 months follow-up of 15 cases,the patients′ renal function had been improved with no stricture of the ureter.Conclusion As a minimally invasive technique,retroperitoneoscopic ureterolithotomy is proved to be a safe and effective to the treatment of ureter stone.It can take the place of conventional open surgery in part.