Aging is an important risk factor for many metabolic disorders，including obesity，impaired glucose tolerance，and type 2 diabetes mellitus（T2DM）. It is reported that the incidence of T2DM significantly increases with age. The relevance of this association is dramatically magnified by the concomitant global aging of the population. Insulin resistance and β-cell dysfunction play crucial roles in the age-related impairment of glucose homeostasis. It has great significance in clarifying the pathophysiology of T2DM. Understand－ing the relationship between aging and factors leads to impaired glucose homeostasis such as pancreatic β-cell mass，insulin secre－tion，insulin resistance.