OBJECTIVES To present our surgical techniques and experience with retroperitoneal laparoscopic upper pole nephroureterectomy for a duplex kidney in adult patients without vesicoureteral reflux. METHODS A total of 32 adult patients with a duplex kidney underwent laparoscopic upper pole nephroureterectomy. A 3-port, finger-and balloon-dissecting, retroperitoneal approach was used. The upper pole renal parenchyma was divided circumferentially between the upper and lower poles using a harmonic scalpel, maintaining a margin around the upper pole parenchyma to avoid any possible injury to the lower pole functioning moiety. The urothelium of the remnant upper pole parenchyma was stripped off, and the edges of the remnant upper pole parenchyma were approximated with figure-of-8 stitches. The distal upper pole ureter was mobilized and transected at the point at which the ureter crossed anterior to the iliac vessels. Intravenous urography and renal ultrasonography were performed at 3 and 6 months postoperatively. RESULTS All laparoscopic operations were performed successfully without conversion to open surgery. The mean operative time was 83 minutes. The mean blood loss was 18 mL. The mean postoperative hospital stay was 7 days. No intraoperative or major postoperative complications occurred. The intravenous urography and renal ultrasound findings 3 and 6 months postoperatively demonstrated normal pyelography findings and renal function of the preserved lower pole in all patients. CONCLUSIONS Retroperitoneal laparoscopic upper pole nephroureterectomy is a safe and effective procedure and an excellent minimally invasive treatment option for the adult patient with a duplex kidney. UROLOGY 77: 1122-1125, 2011. (C) 2011 Elsevier Inc.