Objective To evaluate the clinical value of pneumatic lithotripsy pressurized flushing system in the treatment of bladder stones with ureteroscopic pneumatic lithotripsy via out sheath of resectoscope. Methods The clinical data of 123 patients with bladder stones who underwent ureteroscopic pneumatic lithotripsy in our hospital in the past 3 years were reviewed. The patients were randomly divided into two groups. The 62 patients in the group A were performed with ureteroscopic pneumatic lithotripsy via out sheath of resectoscope assisted by pressurized flushing system, while the 61 patients in the group B received ureteroscopic pneumatic lithotripsy assisted by Elick suction ball. Three-cavity catheter was routinely indwelt after operation. Operation time, stone clearance rate and postoperative complications were compared between the two groups. Results The lithotripsy was successfully accomplished in all patients and none of the cases was converted to open surgery. The stone clearance time was (24.6 ± 5.1) and (31.2 ± 7.2) min respectively in the group A and the group B (P < 0.05). During the postoperative followup of 3-12 months, none of the patients had stone residue or recurrence through ultrasonography and KUB plain film examination. Conclusions The application of pneumatic lithotripsy pressurized flushing system can shorten the operation time in the treatment of bladder stones with ureteroscopic pneumatic lithotripsy via out sheath of resectoscope. It is a safe and effective method in the treatment of bladder stones, which deserves clinical application in primary hospitals.