The pathological mechanisms of diabetic retinopathy (DR) have always been a research hot topic.It has been believed that retinal microvascular lesions are the earliest pathological change in DR.But recently,studies showed that blood-retinal barrier damage and nerve degeneration also play a decisive role in early DR pathological changes.Some authors found that a large number of apoptotic neurons and activated microglial cells appeared before the retinal microvascular lesions happened.Because early DR analysis is of great value for clinical diagnosis and treatment,this article reviews the research advances in early diabetic retinopathy physiopathology.