Abstract: Objective:To explore the failure causes and countermeasures of ureteroscope pneumatic lithotripsy(URSL).Methods:The failure causes of 12 cases with ureteral calculi treated with URSL were analyzed retrospectively.Results:5 cases with tortuous and narrow ureter and 1 case with ureteral polypus were open surgery.There were 6 cases with stone going up to pelvis or kidney in operation process,and 3 cases with upper stone and 3 cases with middle stone.Six cases with stone going up were treated with placing double J tube and extracorporeal shock-wave lithotripsy.Conclusions:Stone migrations,tortuous or narrow ureters,ureteral perforation and polypus wrapping are the main failure causes of URSL.To raise operating technique andcareful handling can reduce failure.