Severe acute pancreatitis (SAP) is one of the common clinical emergencies, and its clinicopathology is complex and variable, with systemic inflammatory response syndrome (SIRS) and multi-organ failure (MODS) occurring at an early stage, and the morbidity and mortality rate is as high as 36%-50%. Due to the high metabolism and high consumption of SAP patients, protein catabolism is greater than synthesis in the body, and a series of complications occur, so the nutritional support treatment of SAP is often carried out throughout the course of the disease. The following is a summary of the four main points that should be noted in the nutritional support treatment of SAP, hoping to provide help for clinical workers. Parenteral nutrition should be given before SAP patients recover intestinal function in the short term, in order to avoid pancreatic fluid secretion, parenteral nutrition should be given first, with a daily energy supplement of about 32kcal/(kg-d), reduced by 10% for obese people and women, with a caloric to nitrogen ratio of 100kcal:1g or amino acid 1.2 g/(kg-d) as appropriate, with attention to electrolytes and vitamins. The total nutrition mixture should be used for infusion. Long-term total parenteral nutrition (TPN) is likely to cause medical intestinal starvation syndrome, resulting in mesenteric epithelial atrophy, intestinal flora dysbiosis, intestinal barrier destruction, bacterial and toxin translocation and intestinal failure, so it is necessary to transition to enteral nutrition (EN) as soon as possible. Enteral nutrition should be started as early as possible When the disturbance of internal environment in SAP patients is corrected, EN should be started as early as possible once intestinal function is restored. EN can maintain intestinal barrier function and prevent intestinal failure, secondary infection and MODS. Studies have shown that early enteral nutrition can effectively improve the nutritional status of SAP patients and shorten the duration of hospitalization. Usually on the 3rd-7th day of onset, after excluding the underlying diseases such as gastrointestinal bleeding, intestinal obstruction, cardiopulmonary insufficiency, etc., the nutritional status of the patient is assessed and judged according to the actual situation of the patient, and an individualized plan for EN is formulated. the focus at this stage is to increase the nutritional intake, and the total energy is guaranteed to be 30-35kcal/Kg per day in order to obtain energy and positive nitrogen balance. Nutrients are carefully selected for EN and the nutritional formula is gradually transitioned from elemental to whole protein nutrition and supplemented by parenteral nutrition when the body’s needs cannot be met. The transoral diet should start with a small, fat-free, low-protein diet, and gradually increase the amount of food and protein until it returns to normal. The 2013 Chinese guidelines for the diagnosis and treatment of SAP recommend the addition of glutamine to the nutritional therapy of SAP patients. After Meta-analysis, Lu and her team concluded that the parenteral route of glutamine is more effective. The complications of early enteral nutrition are mainly bloating, diarrhea, nausea, vomiting, etc. Besides, the oral, gastric or duodenal administration of nutrients will promote the secretion of pancreatic enzymes and bicarbonate, therefore, it is recommended to place the nutrition tube 20-40 cm below the duodenal Treitz ligament for early enteral nutrition, which can avoid the symptoms caused by nutrient reflux and gastric retention, and will not stimulate the secretion of pancreatic juice. Care should be taken to control the temperature of the nutrient solution (35°C-45°C) to reduce cold stimulation-induced intestinal cramps. The acid in the nutrient solution can cause protein precipitation and lead to blockage of the tube. Warm water should be used to flush the tube before and after the infusion of nutrient solution, and if warm water flushing is not effective, sodium bicarbonate flushing can be used.