The islets are located inside the pancreas, which is both an exocrine gland that secretes digestive juices and a variety of digestive enzymes. The pancreas is also an endocrine gland that secretes a variety of hormones, including insulin. Cell clusters with endocrine function inside the pancreas form pancreatic islets, and the hormones secreted by pancreatic islets mainly include the following: i. Insulin, which is secreted by pancreatic islet β-cells, and is the only hypoglycemic hormone in the body. ii. When various reasons lead to insufficient insulin action, or insulin antagonist hormone increases may occur in abnormal glucose metabolism, or even diabetes. Second, glucagon, glucagon is secreted by the alpha cells in the pancreatic islets, glucagon can raise blood sugar, belongs to the insulin antagonist hormone. Third, growth inhibitor, growth inhibitor is secreted by the pancreatic islet D cells, growth inhibitor on the regulation of blood glucose is smaller. Insulin and glucagon are important hormones that regulate blood glucose and play an important role in maintaining the dynamic balance of blood glucose.