摘要： Objective: To compare Regular and Moses modes of holmium laser lithotripsy during ureteroscopy in terms of fragmentation/pulverization and procedural times in addition to perioperative complications. Patients and methods: After obtaining ethics approval, a prospective double‐blinded randomized trial was conducted for patients undergoing holmium laser lithotripsy during retrograde ureteroscopy. Patients were randomly assigned to either Regular or Moses modes. Patients and surgeons were blinded to the laser mode. Lumenis 120W generator with 200 Moses D/F/L fibers were used. Demographic data, stone parameters, peri‐ operative complications and success rates were compared. The degree of stone retropulsion was graded on a Likert scale from zero‐no retropulsion to 3‐maximum retropulsion. Results: A total of 72 patients were included in the study (36 per each arm). Both groups were comparable in terms of age, and pre‐operative stone size (1.4 vs. 1.7 cm, p>0.05). When compared with the Regular mode, Moses mode was associated with significantly lower fragmentation/pulverization time (21.1 vs. 14.2 min; p=0.03) and procedural time (50.9 vs. 41.1 min, p=0.03). However, there were no significant differences in terms of lasing time (7.4 vs. 6.1 min, p>0.05) and total energy applied to the stones (11.1 vs. 10.8 KJ, p>0.05). Moses mode was associated with significantly less retropulsion (mean grade was 1.0 vs. 0.5, p=0.01). There were no significant differences between both modes in terms of intra‐operative complications (11.1% vs. 8.3%, p>0.05), with one patient requiring endo‐ureterotomy for stricture in the Moses group. Success rate at the end of 3 months was comparable between both groups (83.3% vs. 88.4%, p> 0.05). Conclusion: Moses technology was associated with significantly lower fragmentation/pulverization and procedural times. The reduced fragmentation/pulverization time seen using Moses technology could be explained by the significantly lower retropulsion of stones during laser lithotripsy.