Abstract: Objective:To investigate the necessity of indwelling ureteral stent after middle-lower ureteral calculi treated with ureteroscopic lithotripsy.Methods:One hundred and four middle-lower ureteral calculi patients treated with ureteroscopic lithotripsy were divided into the group A(52 cases,non-indwelling ureteral stent) and group B(52 cases,indwelling ureteral stent).The age,sex,stone size,operative time,postoperative pain,lower urinary tract symptom,gross hematuria,urinary tract infection,stone clearance rate and occurrence rate of postoperative ureteral stenosis between two groups were compared.Results:The differences of the postoperative pain,lower urinary tract symptom,urinary tract infection,gross hematuria,stone clearance rate and occurrence rate of postoperative ureteral stenosis between two groups were not statistically significant(P>0.05).Conclusions:Non-indwelling ureteral stent in middle-lower ureteral calculi treated with ureteroscopic lithotripsy is safe and feasible,which can be decided according to the concrete conditions in clinic.