Sleeve gastrectomy is a gastric reduction surgery mainly for obese patients, which in principle requires longitudinal resection of most of the stomach on the side of the greater curvature, with a resection area of 75%-80%. What is preserved is mainly the gastric lesser curvature, the gastric sinus, the pylorus, and the proximal duodenum of the gastric digestive tract alignment. The remaining volume is about 100-200 ml, forming a small sleeve-shaped stomach, which is required to be able to pass through the catheter as well as to do gastroscopy normally. This procedure does not change the alignment of the gastrointestinal tract, so the postoperative risk is lower and recovery is faster. However, if patients do not restrain their appetite after surgery and still overeat, it is easy to rebound.