Classical glucose-lowering drugs include insulin and oral hypoglycemic drugs. Oral hypoglycemic drugs include sulfonylureas and glinides that promote insulin secretion, biguanides that reduce hepatic glucose output, alpha-glucosidase inhibitors that slow carbohydrate absorption and thiazolidinediones that increase insulin sensitivity. Although these oral drugs have greater or lesser hypoglycemic effects, none of them can control the progression of diabetes. Therefore many patients need to receive a combination of different mechanisms of glucose-lowering drugs as their blood glucose continues to rise, and eventually change to insulin to lower their blood glucose. Scientific studies have found that islet B-cell function is only about 50% of normal when type 2 diabetes is diagnosed, and after 6 years of sulfonylurea monotherapy, 62% of patients have only 27% of normal islet B-cell function and need to add other types of hypoglycemic drugs to achieve good glycemic control. From the perspective of glucose-lowering mechanism, DPP-4 inhibitors, by inhibiting the activity of DPP-4 and prolonging the duration of physiological activity of GLP-1, have the effect of inhibiting glucagon while promoting insulin secretion and reducing hepatic glucose output, and also have a variety of beneficial glucose-lowering mechanisms such as appetite suppression and delaying gastric emptying, which can improve glucose tolerance and It can improve glucose tolerance and increase endogenous insulin secretion, thus achieving the purpose of stabilizing blood sugar. Clinical trials have shown that DPP-4 inhibitors have excellent glucose-lowering effects, and the incidence of hypoglycemia is comparable to that of placebo, demonstrating the good hypoglycemic safety of these drugs. In conclusion, DPP-4 inhibitors break through the limitation that previous hypoglycemic drugs have no effect on B-cell function, with excellent hypoglycemic effect and high safety, which can effectively slow down the progression of diabetes, and some experts call it a new milestone in the field of diabetes treatment.