 Type 2 diabetes is associated with a markedly increased risk for atherosclerotic coronary arteries and cerebrovascular diseases. The major cause of death in diabetic patients is cardiovascular disease in the world including Taiwan. Atherosclerosis is a progressive disease characterized by the response of the vessel wall to chronic, multifactorial injury, which leads ultimately to the formation of atheromatous or fibrous plaques. Endothelial dysfunction is thought to be the initial stage of atherosclerosis. Endothelial dysfunction leads to impaired control of vascular tone, a decreased in the release of anti-inflammatory factors and reduced availability of nitric oxide. Endothelial dysfunction portends diabetic vasculopathy. The loss of intact endothelial integrity and function sets in motion a cascade of serial events that lead to atherosclerosis and cardiovascular complications. 