The risk of postoperative adhesion formation is a significant concern with transperitoneal laparoscopic surgery. To evaluate the incidence of adhesions after major interventional urologic laparoscopy, 16 pigs underwent either laparoscopic (N = 8) or transperitoneal open (N = 8) nephrectomy. Adhesions occurred at 12.5% of the operative sites in the laparoscopic group compared with 75% of the operative sites of the open group. Adhesions were present along the incision site in all the pigs in the open group compared with 5 of 40 (12.5%) trocar sites in the laparoscopic group. Adhesion number, grade, and extent were significantly greater in the open group than the laparoscopic group for both nephrectomy and access (incision/trocar) sites (p < 0.05). Transperitoneal laparoscopic urologic surgery in the porcine model results in a marked decrease in adhesion formation compared with incisional transabdominal surgery.