Nutritional support is one of the most important surgical advances since the last century, and after years of development and improvement, various nutritional support techniques have become increasingly mature. Giving parenteral nutrition to patients who cannot eat by mouth, have gastrointestinal obstruction or absorption dysfunction is the conventional treatment at present, but with the depth of research, it is gradually recognized clinically that the gastrointestinal tract is not simply a digestive and absorption organ, but also has an important immune role, and enteral nutrition can be more physiologically compatible and maintain the intestinal barrier function when the intestine can be used effectively. This is particularly important for perioperative patients. According to statistics, more than half of the hospitalized patients have different degrees of malnutrition, and the effective application of enteral nutrition support is an important guarantee for smooth recovery before and after surgery and for critically ill patients. Since 2000, our department has been carrying out enteral nutrition support for major surgeries such as gastric cancer, intestinal cancer, liver cancer, liver transplantation and other critical patients, and has completed the placement of jejunal nutrition tubes through intraoperative placement, gastroscopic or X-ray guided placement of nasal intestinal tubes, percutaneous gastrojejunostomy and other methods. So far, we have completed more than 5,000 cases of enteral nutrition support, ensuring the perioperative safety of a large number of patients and saving the lives of many critically ill patients, and our overall treatment level is among the leading ones in China. Attachment: Nutritional Treatment Guidelines (Chinese Society of Enteral and Parenteral Nutrition)