Teenagers with myopia of 400 degrees in one eye and normal in the other eye may be caused by refractive error, which can be corrected by wearing glasses and masking therapy. 1. Wearing glasses: teenagers with myopia of 400 degrees in one eye and normal in the other eye are advised to go to the hospital for optometry, and under the guidance of the doctor, according to the difference between the degrees of the two eyes, the corresponding treatment can be done, and contact lenses can be worn to correct monocular vision, so as to avoid strabismus and amblyopia and other conditions. 2. Covering therapy: young patients with refractive amblyopia can use black eye masks or other coverings to tightly cover the eyes with better eyesight, forcing the amblyopic eye to look at it, so that it can be exercised, gradually slowing down or eliminating the inhibitory effect of the better eye on the amblyopic eye, and thus improving the vision. Teenagers with myopia of 400 degrees in one eye and normal in the other, it is recommended to go to the hospital in a timely manner, after clarifying the cause of the disease, according to the doctor’s guidance for standardized treatment.