Abstract： Background Laparoscopic dismembered pyeloplasty with less trauma than open surgery is commonly performed for ureteropelvic junction obstruction despite a longer operating time and a long learning curve. We describe in this paper a new technique, which combines laparoscopic and open procedure in dismembered pyeloplasty, that we have developed in 51 patients and achieved excellent results.Methods The surgical procedure can be divided into two steps: laparoscopic dissection of the renal pelvis and proximal ureter transperitoneally; then accomplishing the pyeloplasty through the extended port incision above the ureteropelvic junction as in open surgery.Results All 51 operations were successful without conversion to open surgery. No intraoperative complications were observed. The operating time was 40 minutes to 90 minutes with an average of 57.5 minutes. The estimated blood loss was 15 ml to 30 ml with an average of 21.2 ml. Aberrant artery vessel and primary stricture as the cause of ureteropelvic junction obstruction was noted in 2 and 49 patients, respectively. Thirty-nine patients had fever to differing extents in the 4 days postoperation and no severe infection was observed. Four patients had urinary leakage with their drains being retained for 6 days, 6 days, 5 days or 8 days after the operation. The mean followup was 10.8 months (range 3 months to 36 months). The followup showed good results with symptom resolution in all the patients. Renal ultrasonography demonstrated that the average separation of the collecting systems decreased from preoperative 2.7 cm (range 2.0 cm to 4.7 cm) to postoperative 1.5 cm (range 1.0 cm to 2.3 cm). Excretory urography at 3 months postoperatively showed improved drainage. Of the 51 patients, 35underwent two or more excretory urograms, demonstrating stable renal function, improved drainage and no evidence of recurrent obstruction. At the last followup visit, each patient was doing well.Conclusions Combination of laparoscopic and open procedure in dismembered pyeloplasty offers a simpler,timesaving method in a minimally invasive fashion with low morbidity for patients with ureteropelvic junction obstruction. Ensuring quality of repair, the method provides a minimally invasive alternative with good results. It is worth future clinical application.