Abstract: Diabetic retinopathy is a major cause of visual impairment. In recent years, some studies showed that the damage of retinal neurons can be detected earlier than microangiopathy in diabetic patients and animal models as well. Detect and treat retinal lesions at an early stage are essential for protecting patients’ visual functions. The pathogenesis of retinal neuron lesions is complex. Oxidative stress, advanced glycation end products, glutamate excitotoxicty, and inflammation all involved in the disease. In this paper, we reviewed the retinal neuron damage in early diabetes and its pathogenesis.