Abstract: Objective To evaluate the efficacy and safety of ureteral occlusion device used in ureteroscopic holmium laser lithotripsy for treatment of upper ureteral calculi.Methods 120 patients with upper ureteral calculi were randomly divided into two groups：60 patients were treated  with ureteral occlusion device（test group），and 60 patients were treated without ureteral occlusion device（control group），and the efficacy and safety were observed.Results The primary calculus elimination rate，the length of stay hospital and post-operative stone-free-rate in test group were significantly better than those in control group：93.3% vs.78.3%，（2.5±0.4)d vs.(3.7±0.6)d，96.7% vs.86.7%，and there were significant differences（P<0.05）.There was no significant difference in surgical complications between the two groups（P＞0.05）.Conclusion The blocking catheter combined with holmium laser lithotripsy under ureteroscopy can reduce the drift of upper ureteral calculi, improve the clearance rate of calculi and shorten the hospital stay.

Key words: ureter calculi, ureteroscopy, lithotripsy, ureteral occlusion device