The eyes of young children all have a developmental process from low norm to normal. Although children can measure their visual acuity from the age of 3, they usually perform below the normal standard. vision at the age of 1 is about 0.1~0.3, normal vision at the age of 3 is about 0.6, normal vision at the age of 4 is about 0.8, and normal vision at the age of 7 should be 1.0. the determination of vision chart is a primary perception check, especially for children, and there are many influencing factors, so conclusions cannot be easily drawn. Preschoolers’ visual acuity is also divided into distance vision and near vision. At present, some kindergartens and families generally strengthen the cultural education of children, increasing the visual burden of young children, eye regulation tension, it is easy to show low vision (i.e. myopia), but most of them are pseudomyopia, that is, no treatment or treatment is needed, most of them can recover on their own.” How can preschoolers use their eyes scientifically to protect their vision? The first step is to have the right brightness of ambient light, for example, when going out, it is best to avoid direct sunlight. Indoor strobe-free lighting is best for protecting vision; Secondly, attention needs to be paid to near eye posture, and it is important to develop good reading and writing habits. It is very important to develop good reading and writing habits. Children should read in a correct sitting posture, keep a distance between books and eyes, avoid looking down or up when watching TV, do not lie in bed or read in a moving car; again, shorten the time spent in close proximity to the eyes, learn to control children at home to look at the computer, watch TV or other activities that will increase the burden of vision. When using the eyes at close range, take a 15-minute break every 40 minutes; and finally, increase outdoor activities. When exercising, the eyes will have more time to look away while promoting physical health, and it will also help the eyes relax. Preschoolers do not have a strong sense of self-control, so parents and teachers need to help children take care of their eyes. The key is to pay attention to the above points and stick to them, otherwise it will be more difficult to change the good habits if they are not formed at this time. If the following conditions are found, most of them are abnormal: visual acuity is less than the visual acuity of the same age, bilateral visual acuity is asymmetrical, optometry shows pathological refraction, etc. Parents and teachers should detect eye diseases in time for early detection and treatment.