Objective To investigate the effect of transurethral holmium YAG laser in treatment of bladder calculi.Methods F5 laser fiber in the holmium YAG laser was used to treat 40 patients with bladder calculi.Then the effect was observed.Results All 40 cases were successfully done by the operation time range from 15 to 120 minutes.There were no major complications,such as TRUS,bladder rupture or major bleeding.There was no residue stone.Conclusion F5 laser fiber in the holmium YAG laser treatment could be protected by the transurethral scope.It was safe,effective and has shorter operation time in treatment of bladder calculi.