Abstract: Diabetic retinopathy (DR) is an important cause of vision loss and blindness in diabetic patients. Studies have shown that neurodegenerative changes have occurred before diabetic retinal microvascular injury, such as reactive glial increase and ganglion cell apoptosis, and endoplasmic reticulum stress is involved in this process.Studies have shown that neurodegenerative changes have occurred before diabetic retinal microvascular injury, mainly as ganglion cell apoptosis, and endoplasmic reticulum stress is involved in this process.The UPR has three signal paths:the ATF6 signal path, the PERK signal path, and the IRE1 signal path.It is closely related to oxidative stress, inflammation, apoptosis, BRB destruction and angiogenesis in the DR process.Exploring the intrinsic mechanism of ERS and ganglion cell injury is of great significance for finding new effective drugs to prevent or treat diabetic patients.