Abstract: For rhesus monkeys, maternal separation (MS) is often used to mimic childhood adversity in humans, which can lead to brain dysfunction and, as results, behavioral abnormalities. People who suffer from psychiatric disorders due to childhood adversity usually  lived a normal social life prior to the onset of the diseases. Instead, the effects of MS on rodents could be reversed by later experience. In order to identify whether the adverse effects of MS were reversible by later normal social living in rhesus monkeys, we conducted a long-term study and established an animal model for human early adversity in rhesus monkeys. The results showed that MS lead to dysfunction of HPA axis which helps manage stress and resulted abnormal behaviors in these rhesus monkeys. Furthermore, the normal social life appeared not to have obliterated the imprints of MS, suggesting that the effects of MS are long-lasting. Thus, compared to rodent models of MS, the maternal separated rhesus monkeys are a more suitable animal model to study the effects of childhood adverse experiences among people and to investigate the development of psychiatric disorders induced by exposure to childhood adversity.