Objective To investigate the clinical efficacy and safety of flexible ureteroscope combined with holmium laser in the treatment of upper urinary tract calculi(≥2.0cm).Methods One hundred patients with upper urinary tract calculi (≥2.0cm) were divided into control group and observation group according to random digits table method with 50 cases each.The control group was treated with percutaneous nephrolithotomy combined with holmium laser,and the observation group was treated with flexible ureteroscope combined with holmium laser.The operation related index, stone clearance rate and postoperative complications were compared between 2 groups.Results The operation time, two stage stone removal rate and length of hospital stay in observation group were significantly lower than those in control group:(45.76 ± 9.24)min vs.(52.12 ± 10.68)min,2.00%(1/50) vs.16.00%(8/50)and(4.46 ± 1.22)d vs.(5.73 ± 1.91)d,and there were statistical differences(P<0.01 or <0.05).The stone clearance rate in observation group was significantly higher than that in control group:94.59%(70/74)vs.81.69%(58/71),and there was statistical difference(P<0.05).There was no statistical difference in incidence of postoperative complications between 2 groups (P>0.05).Conclusions Flexible ureteroscope combined with holmium laser in the treatment of upper urinary tract calculi (≥2.0cm) can effectively reduce the reoperation rate, shorten the operation time and hospitalization time,and improve the stone clearance rate.The treatment is safe and effective.