Atherosclerosis is thought to arise as a result of a chronic inflammatory process within the vessel wall,also the basic pathology of cardiovascular disease.Clinical studies found that pioglitazone,a peroxisome proliferator-activated receptor gamma agonist,can improve glucose and lipid metabolism,protect vascular endothelial function,reduce inflammatory markers,inhibit smooth muscle cell proliferation,anti-thrombosis,stabilize atheromatous plaque and so on,which plays a protective role in the pathological process of atherosclerosis and prevention of vascular disease,reduces the incidence of cardiovascular events and mortality.In this paper,the mechanism of the effect of pioglitazone on anti-atherosclerosis is reviewed.