Abstract:【Objective】 To discuss the safety and feasibility of the low pressure flush percutaneous nephroscope ultrasonic lithotripsy . 【Methods】 48 cases of renal and ureteral calculi were treated by percutaneous nephrolithotomy (24 F) standard channel stone treatment ultrasound lithotripsy. All patients were flushed with the bag of physiological saline, perfusion pressure was maintained at 30~50 cmH2O, and the maximum of renal pelvic pressure was measured.【Results】 Intraoperative maximum renal pelvic pressure was 23 cmH2O. The operative field is clear, 3 cases of postoperative fever, T was 38.5℃, the remaining patients with T<38.5℃, no urinary sepsis. After 2 to 4 weeks CT, B ultrasound or X-ray examination, the stone free rate was 95.83% (46/48). 【Conclusion】 Percutaneous nephroscope ultrasonic lithotripsy taking standard channel and saline low pressure flush is safe and feasible, which has a good clinical application value.