OBJECTIVE A retrospective study was performed to compare the results of laparoscopic pyeloplasty and antegrade endopyelotomy and complications observed after the two procedures. METHODS Seventy-five endopyelotomies and 90 laparoscopic pyeloplasties in patients with primary ureteropelvic junction obstruction (UPJO) were performed. The diagnosis of UPJO was based on a complete medical history, ultrasonography, urography (IVU), and/or diuretic renography. In 52 cases, a Whitaker test was performed before endopyelotomy. The mean follow-up was 31 months in the endopyelotomy group and 28.5 months in the laparoscopy group. Complete success was defined as absence of any clinical symptoms combined with significant reduction of hydronephrosis on diuretic IVU and ultrasonography, and no sign of obstruction on diuretic IVU, diuretic renography, or Whitaker test. RESULTS Complete success was observed in 55.4% of patients after endopyelotomy and in 95.3% of patients after laparoscopic pyeloplasty. In patients with primary UPJO, laparoscopic procedures yield better therapeutic results than endopyelotomy, irrespective of the degree of hydronephrosis. The number of complications after the two procedures was comparable with the exception of intraoperative bleeding, which was more frequent in the case of endopyelotomy. CONCLUSIONS Laparoscopic pyeloplasty should be the procedure of choice in the treatment of primary UPJO.