Diabetic retinopathy is a part of diabetic systemic small vessel lesion, which is irreversible vascular damage and is the main cause of blindness. Its severity depends mainly on the duration of the disease, and the status of blood glucose control, and must be examined, detected and treated early. In China, diabetic retinopathy is divided into two categories: non-proliferative (background) and proliferative: 1. non-proliferative Stage I microangioma or full and small hemorrhages Stage II hard exudate combined with stage I lesions Stage III cotton wool spots combined with stage II lesions 2. proliferative Stage IV optic disc neovascularization or full and vitreous hemorrhages Stage V fibrovascular proliferation, vitreous mechanization Stage VI retinal detachment of retinal traction Diabetic retinopathy Prevention and treatment: 1. Control blood glucose in the normal range with diet or combined hypoglycemic drugs as much as possible. When oral drugs cannot lower high blood glucose, insulin injection is needed actively according to the instruction of endocrinologist. 2, non-proliferative retinopathy in addition to strict control of diabetes, can be used dihydroxybenzene sulfonate calcium drugs such as guide ascorbic acid to reduce the high leakage response of retinal blood vessels in diabetes, reduce the high viscosity of blood and reduce the high aggregation of platelets. A low-fat, high-protein diet and the use of more vegetable oils can reduce the hard leakage from the fundus. Diabetic patients are often combined with hypertension and/or hyperlipidemia. In controlling hyperglycemia, treatment of hypertension and hyperlipidemia should be taken into account at the same time to lower them to normal level. 3.Laser treatment can effectively stop the development of retinopathy. 4. In advanced proliferative diabetic retinopathy, serious vitreous hemorrhage may occur, and the unabsorbed hemorrhage may form mechanized membrane or strips in the vitreous, which may cause macular edema, macular ectasia, or even retinal detachment by traction. The only treatment at this time is vitrectomy, which removes the accumulated blood and decomposing material and cuts off the mechanized membrane, then aspirates the fragments to eliminate the scaffold on which the fibrous tissue grows, loosens the pull on the retina, and injects liquid and/or gas to restore the normal retinal anatomy and keep the eye intact for laser photocoagulation or condensation.