We here overviewed the current evidence for the clinical feature and the mechanistic insight of glucose intolerance in the elderly. Prevalence of glucose intolerance progressively increases in age, and postprandial hyperglycemia is a common feature of glucose intolerance in the elderly. Glucose intolerance in the elderly is associated both with impaired insulin secretion and insulin resistance. The change in the physical composition including sarcopenia and sarcopenic obesity is likely attributable to the development of insulin resistance observed in the elderly. Moreover, the dysfunction of mitochondria and the decline in the activity of certain hormones also appear to contribute to the pathogenesis of glucose intolerance in the elderly.