The hormones that regulate blood glucose mainly include insulin, glucagon, catecholamines, glucocorticoids and so on. Among them, insulin and glucagon are the most important. Insulin is a hypoglycemic hormone secreted by pancreatic beta cells, and insulin is the only hypoglycemic hormone in human body. Glucagon is a blood sugar-raising hormone secreted by pancreatic alpha cells, which promotes insulin secretion when blood sugar rises. Insulin can promote cellular uptake, inhibit the conversion of glycogen into glucose using glucose, inhibit the breakdown of protein and fat, and reduce gluconeogenic raw materials to further lower blood sugar. High blood glucose can also inhibit glucagon secretion to avoid further increase of blood glucose. When blood glucose decreases, it will reduce insulin secretion and stop insulin secretion when blood glucose is lower than 1.67mmol/L, while promoting glucagon secretion. Glucagon can promote glycogen decomposition into glucose, maintain blood glucose concentration, and promote protein and fat decomposition to provide gluconeogenic raw materials. At the same time, catecholamines and glucocorticoids are elevated during hypoglycemia, and cooperate with glucagon to raise blood glucose.