Diabetic kidney disease (DKD) is one of the leading causes of chronic kidney disease (CKD) and end-stage renal disease (ESRD) worldwide. With the overpowering trend of aging, the prevalence of DKD in the elderly is progressively increasing. Genetic factors, abnormal glucose metabolism, inflammation, mitochondrial dysregulation, and oxidative stress all contribute to the development of DKD. Conceivably, during aging, these pathobiological processes are likely to be intensified, and this would further exacerbate the deterioration of renal functions in elderly patients, ultimately leading to ESRD. Currently, the pathogenesis of DKD in the elderly is not very well-understood. This study describes an appraisal of the relationship between diabetic nephropathy and aging while discussing the structural and functional changes in the aged kidney, the impact of related mechanisms on the outcome of DKD, and the latest advances in targeted therapies.