It is not normal for a 7 year old child to have a visual acuity of 4.8. A child’s normal visual acuity should be 4.9 and above in one eye. A 7 year old child with lower than normal visual acuity is not necessarily myopic. 7 year old children’s eye axis has not yet developed into the length of a normal adult, the minimum visual acuity should not be lower than 4.9, if the visual acuity is lower than normal, there may be myopia, hyperopia, astigmatism or amblyopia, the above conditions may cause the child’s eyesight to decline. In this case, it is best to take the child to the hospital ophthalmology consultation in a timely manner, the first test 5 meters of naked eye visual acuity, and then dilated optometry, to check whether there is myopia or astigmatism, and then according to the results of the examination in a timely manner to give positive treatment. In addition, 7-year-old children must sit properly, less look at electronic products, do eye exercises on time, can effectively avoid or reduce the occurrence of myopia.