Glucose tolerance test, i.e. glucose tolerance test, the process is that after fasting for more than 8~10 hours, an aqueous solution containing 75g of anhydrous dextrose is given orally to adults, and 1.75g per kilogram of body weight for children (the total amount is not more than 75g), and the fasting blood is drawn before taking the glucose (0min), and then the blood is collected at 30min, 60min, 120min, and 180min respectively after taking the glucose and the changes of its blood glucose are measured. Oral glucose tolerance test is a glucose load test to understand the function of pancreatic β-cells and the body’s ability to regulate blood glucose, and it is a confirmatory test for the diagnosis of diabetes mellitus, widely used in clinical practice. It should be noted that patients should stop taking diuretics and contraceptives 3-7 days before the test, and the diet should contain at least 150 grams of carbohydrates per day for three days before the test. Fasting is required for 8~10 hours before the test, and fasting is also required on the morning of the test. Smoking, alcohol, coffee and tea are prohibited during the test, and strenuous exercise is not allowed. The process of glucose tolerance test is summarized as fasting, drinking sugar water, and blood test. For more medical knowledge, we recommend consulting a specialist.