There is no clear standard for gastric cancer wasting, and it needs to be analyzed according to the patient’s basic nutritional status, weight loss rate and so on. Basic nutritional status: according to the standard of nutrition, the fatness and thinness of adult patients are measured by BMI (Body Mass Index), the calculation of BMI is weight/height^2, and wasting level refers to BMI<18.5. Rate of weight loss: Gastric cancer is a common malignant tumor of the digestive tract, and patients can have nausea, vomiting, decreased food intake and other manifestations. With the progress of the disease, patients can show weight loss and malnutrition, and the rate of weight loss can reach 1-2kg per week in serious cases. There is no uniform standard for the wasting status of gastric cancer patients, so they need to visit specialized hospitals regularly and make nutritional treatment plan under the guidance of gastroenterologists and nutritionists if necessary.