The aging kidney is a complex and multifactorial process. As for a large portion of the elderly, declining glomerular filtration rate (GFR) is an inevitably phenomenon because of structure and function changes within kidney aging, including glomerulosclerosis, tubular atrophy, fibrosis, vascular changes and endocrine deficiency. Other factors such as gender, genetic, oxidative stress, impaired repair ability and cardiovascular disease also influence declined renal function and promote renal apoptosis. However, about one-third of the elder individuals still maintain their GFR constantly. To understand about aging process, we may prevent the GFR decline rate and diminish the unnecessary medical treatment.