Exosomes are extracellular vesicles with a diameter of 40-100 nm, which contain a variety of functionally active substances such as proteins, microRNAs, and they are transported into the cell via different pathways. Studies have confirmed that exosomes slow down the progression of diabetic retinopathy by modifying changes in the levels of cell proliferation/apoptosis factors, antioxidant regulatory factors, inflammatory factors, and vascular endothelial growth factor in different ways, including direct regulation and delivery of different miRNAs, long-chained noncoding RNAs, which in turn inhibit high-glucose-induced retinal inflammation, neovascularization, microvascular damage, and vascular leakage and other retinal injuries caused by high glucose. This review summarizes the basic characteristics of exosomes and their research progress in diabetic retinopathy.