Between February 1994 and February 1995, we performed retroperitoneal laparoscopic pelvic lymphadenectomy on 7 patients with prostate cancer between 63 and 76 years old, consisting of 6 patients with clinical stage B2, and 1 patient with stage C. Retroperitoneal laparoscopic procedures were performed under general anesthesia. First, the prevesical space was separated by a balloon dissector to create the working space. Then, three trocars were inserted into the retroperitoneal space at the lower abdominal midline. Except for the first patient, only two surgeons were needed to dissect the obturator lymph nodes, under 5 mmHg CO2 insufflation. The mean operating time was 133 minutes for bilateral lymphadenectomy. The mean number of removed lymph nodes was 4.8 on the left side and 4.2 on the right side. The estimated blood loss ranged from 10 to 66 ml. As none of the patients showed node involvement on the microscopic examination of the frozen section, they immediately underwent total prostatectomy. Additionally removed lymph nodes were 0.8 on the left side and 1.5 on the right side. As for intraoperative complications, endotidal CO2 was elevated in the first patient, but the other patients had no complications. Retroperitoneal laparoscopic pelvic lymphadenectomy is a safe and useful procedure, and may facilitate a lymphadenectomy better than a peritoneal procedure.