We used the conventional medial approach with five-port to perform laparoscopic total mesorectal excision. In the medial dissection, an incision was made at 2 cm on the inside of the ureter and the left Toldt space was entered and expanded from the caudal to the cephalicl end by sharp dissection. In this process, lymphadenectomy was performed at the root of the inferior mesenteric artery. Meanwhile, the roots of the left colic artery and the sigmoid artery were exposed and dissected. The root of the inferior mesenteric vein was ligated and cut at the left side of the ligament of Treitz. According to an inside-to-outside approach, we further expanded the left retrocolic space and the retro-rectosigmoid space. The process must be careful to protect left ureter and reproductive artery against injury. Dissection was made along the mesocolon transversum, while exposing and ligating at the root of the middle colic artery at the lower edge of the pancreatic head. The gastrocolic ligament was exposed along the greater curvature from the middle to the distal end, and the left gastroepiploic artery was also exposed and then ligated and cut. Finally, the left colon and its mesentery were separated completely. A 5 cm abdominal incision was made on the left lower quadrant. The left colon was resected in vitro, including the tumor, the colic mesentery and the proximal and distal part of the colon. An extracorporeal functional end-to-end colon anastomosis was performed via the 5 cm incision. After a drainage tube was placed, the abdominal incision was sutured.