It is generally recognized that a 9 year old child’s visual acuity of 4.8 is a bit on the low side and is considered to be low vision. Generally speaking, adult visual acuity of 5.0 and above is considered normal vision. Combined with the age, children aged 8-9 years old can develop to a visual acuity of 5.0, and the child’s visual acuity of 4.8 at the age of 9 years old is considered to be low vision. There are many reasons for low vision, such as nearsightedness, farsightedness, astigmatism or amblyopia, etc. It is necessary to go to the hospital for pupil dilation and optometry to determine the specific cause of the problem and then actively correct it. Parents should pay attention to their children’s vision protection, take their children to participate in sports activities, do eye exercises more often, and actively go to the hospital for further examination to avoid delaying the condition. It is recommended that children with vision loss consult a doctor in time to assess their condition and follow the doctor’s instructions for treatment.