Poor vision (also known as low vision, poor vision) is usually defined as poor vision when the vision is checked by a distance visual acuity meter and the distance visual acuity of any bare eye is less than 1.0 (logarithmic visual acuity 5.0). Among primary and secondary school students, 80-90% of poor vision is myopia. The factors of myopia formation are complex, mainly four factors: genetic factors, behavioral factors, environmental factors, and physical factors. Therefore, establishing good eye hygiene behavior, improving eye environment, and enhancing physical health are the main measures to prevent the development of myopia in adolescents.