Exosomes are small extracellular vesicles secreted by cells and carry many biological molecules, such as mRNA, microRNA, proteins, and transcription factors.Exosomes play a role in mediating intercellular communication in normal physiological processes.In the pathological state, they can mediate pathological processes, such as endothelial cell damage, vascular inflammation, and blood-retinal barrier (BRB) dysfunction.Exosomes play an important role in the progress of diabetic retinopathy (DR). With a wide range of sources, circulating exosomes are closely related to the basic metabolic state of the eye and the body.They have many biological information and can be used as a source of early diagnosis markers for DR.In the diabetic state, circulating exosomes are involved in the transport of inflammatory factors and angiogenic factors, which activates endothelial cells and thereby destroys the BRB.Exosomes might be a new therapeutic target for DR.Eye-derived cells are involved in cell proliferation and angiogenesis by secreting exosomes.Retinal pigment epithelial cell-derived exosomes can promote angiogenesis in vitro, helping to reveal the mechanism of DR neovascularization.This article reviews the relationship between exosomes and DR diagnosis, pathogenesis, and treatment, which may provide a new insight into the pathogenesis and treatment strategy of DR.