Long-term poor glycemic control of diabetes can lead to a variety of complications arising from the heart, brain, kidneys, nerves, and the fundus of the eyes. The eye symptoms caused by diabetes mainly include the following: First, retinopathy, retinopathy is a microangiopathy unique to diabetes, which can manifest as retinal hemorrhage and exudation, affecting the patient’s vision. In severe cases, there will be neovascularization and retinal detachment, which can lead to blindness. Second, cataract, long-term high blood sugar can lead to lens clouding and diabetic cataract. Third, diabetes can cause macular degeneration and macular edema. Diabetes can also lead to glaucoma, or aggravation of the existing glaucoma symptoms. Diabetes can cause conjunctival congestion, conjunctivitis and other eye irritation symptoms, and can also lead to changes in atrial osmotic pressure, resulting in visual fatigue.