As the natural orifice during embryonic, the transumbilical surgery not only can mask the abdominal scar and avoid infection produced by puncturing stomach, vagina or rectum in NOTES,but also can be played by the conventional laparoscopic instruments. TU-LESS (transumbilical laparoendoscopic single site surgery), is considered to be the most feasible NOTES(natural orifice transluminal endoscopic surgery)technology at present. Researches about TU-LESS mostly are case reports and small samples or the control experiments up to now,there are not persuasive randomized controlled trail between TU-LESS and conventional laparoscopic cholecystectomy. So the investigators design this prospective randomized controlled trail to scientifically evaluate the safety, efficacy and cosmetic results of transumbilical laparoendoscopic single site cholecystectomy .