Many people know that myopia is caused by reading books, playing with cell phones and other distances too close, not wearing the right glasses after myopia, and not enough outdoor activities, so sit and work, study to have a good posture, keep enough distance to see things; teenagers should participate in more outdoor activities; myopia should be standardized after the glasses. These instructions are like the Chinese duck-and-egg education, which is not well understood and often not understood in practice, as if they have been done, but do not get the expected results. We need foreign-style cognitive education to analyze the problem clearly, the causes and consequences are straightened out, the overall understanding is thorough, what to do and what to pay attention to can be well grasped, even when encountering different situations, the reasoning is the same and can be done well, prevention and control of myopia need to be so good in every detail. Visual fatigue is a key factor in the development of myopia, for the relief of visual fatigue did not do a good job, the occurrence and development of myopia in adolescents. Adolescents are in an important stage of development, the eye has plasticity, often different stimulation of the eye, there will be different results, the result of long-term visual fatigue is the occurrence of myopia, and myopia degree continues to deepen. Various stimuli that lead to visual fatigue, such as prolonged close eye use, ciliary muscle contraction for a long time is easy to visual fatigue; myopia after not wearing the right number of glasses, will unconsciously squint to see things, eye cluster tension, but also easy to visual fatigue. In the state of visual fatigue, the brain believes that the eye is not long enough and needs to continue to grow, and will secrete hormones to continuously stimulate the eye to grow longer. This firing of the brain would have been normal because at birth, the eyeball is about 16mm in length, in a farsighted state, and needs to grow to 24mm in an orthogonal state. The length of the eyeball does not recede, but only grows longer and longer. The development of the eyeball usually stops by the age of 20, and any over-stimulation of the eyeball before then grows too fast to form myopia. So the treatment of farsightedness needs to give the farsighted eye fatigue stimulation, common is to wear beads; and the prevention and control of myopia needs to give the eye relaxation, the most simple and easy is to increase outdoor activities, a variety of myopia therapy device, massage therapy, drugs are nothing but to give the eye relaxation. For teenagers in order to prevent myopia, in addition to not using eyes for a long time at close range, appropriate outdoor activities, need to regularly measure vision, if vision is not up to standard, need to check the shadow optometry, if there is more than 100 degrees of myopia, in addition to close eye (such as reading books, reading computers, etc.) need to wear glasses; or in the early myopia for standardized foggy vision treatment, to reduce the development of myopia is also helpful.