Objective To investigate the feasibility and safety of endoscopic treatment of ureteral calculi acute obstruction with urinary extravasation. Methods 56 patients with ureteral calculi acute obstruction and urinary extravasation were randomly divided into two groups:the treatment group and the control group,28 cases in each group. Patients in the treatment group were given URSL or percutaneous nephrostomy drainage, and the secondary fistula was given URSL stone clearance treatment. Patients in control group were given traditional ureterolithotomy treatment. The stone clearance rate, the average recovery time after surgery, postoperative wound infection rate and the abnormal rate of postoperative albumin were observed in two groups. Results In the treatment group,28 patients had no residual stones with mean postoperative recovery time of (5.2 1.3) days,postoperative fever was found in 3 cases,obvious abnormal postoperative albumin in 3 cases. In the control group,residual stones were found in 3 cases,the average recovery time after surgery was (7.9 2.6) days,postoperative fever was found in 10 cases, and obvious abnormal postoperative albumin in 11 cases. There were statistically significant differences in stone clearance rate, the average recovery time after surgery, postoperative wound infection rate and the abnormal rate of postoperative albumin between two groups (P<0.05) . Conclusion Endoscopic treatment of ureteral calculi acute obstruction and urinary extravasation has advantages including better efficacy, less trauma, less complications and quicker recovery.