Eye fatigue and blurring may be caused by visual fatigue, refractive error, cataract and glaucoma. 1. Visual fatigue: If you study or work too long, and look at your cell phone for a long time or stay up too late, it will easily lead to a decrease in your eyesight and blurred vision, commonly known as visual fatigue, which is a common eye problem. 2. Refractive error: If you have myopia, hyperopia or astigmatism, objects refracted by the refractive system will focus on the front or back of the retina, resulting in blurred vision and the symptom of not being able to see clearly. 3. Cataract: In the initial stage of cataract, the patient will have myopia of crystalline origin, which leads to blurred vision and great eye fatigue. 4. Glaucoma: The circulation of aqueous humor in the patient’s eye is blocked, leading to increased intraocular pressure and optic nerve damage. Acute episodes of glaucoma can be characterized by blurred vision, accompanied by nausea, eye swelling and pain. Patients with symptoms of eye fatigue and blurring should go to the hospital in a timely manner to clarify the cause of the disease and receive proper treatment under the guidance of the doctor.