African Green monkeys (AGM, Chlorocebus aethiops sabaeus) are commonly used as animal models in research, such as in hypertension and SARS-Covid 2019. There is scant information describing background and spontaneous lesions in aged AGM population. In a group of 32 AGMs, 65.6% were presented with renal histologic changes. The most common changes encountered were interstitial nephritis, glomerular sclerosis and fibrosis and multiple cortical cysts. We believe that identifying histologic changes in aged AGMs will assist researchers in better understanding and characterizing spontaneous and disease associated renal lesions