Fibroblast growth factor 21 (FGF21) is a newly discovered metabolic regulatory factor in recent years. The relationship between FGF21 and diabetic macroangiopathy has become a research hotspot in recent years. The level of endogenous FGF21 is increased in patients with impaired glucose tolerance, and its level is progressively increased with the appearance of type 2 diabetes mellitus with macroangiopathy. It is speculated that the possible mechanism is FGF21 resistance. FGF21 gene is expressed in vascular endothelial cells, and FGF21 may play a protective role in the early stage of atherosclerosis, suggesting that FGF21 is expected to become a target for prevention and treatment of diabetic macroangiopathy.