Abstract: Niemann-Pick C1 Like 1 (NPC1L1) plays a decisive role in ezetimibe in lipid-lowering therapy. Ezetimibe can reduce serum dipeptidyl peptidase 4 (DPP-4) activity and increase the activity of serum glucagon-like peptide 1 (GLP-1), thus controlling blood glucose to a certain degree in diabetic patients. Clinical studies have shown that ezetimibe can lower lipid levels, prevent coronary heart disease (CHD) and reduce the incidence of cardiovascular diseases, especially in patients with CHD complicated with diabetes. In recent years, more in-depth research has been conducted concerning the roles of NPC1L1, GLP-1 and DPP-4 in patients with CHD complicated with diabetes.