A 6-year-old child with a visual acuity of 4.9 does not reach the normal standard, which is close to normal, probably because of relatively delayed visual development and possible myopia. Generally speaking, the normal development of children’s vision follows a certain pattern, at about 3 years of age naked eye vision should be able to reach more than 4.6, at 4 years of age more than 4.8, at 5 years of age more than 4.9, 6 years of age should be able to reach the same as a normal adult 5.0. However, there are some differences between different individuals, and can not be generalized. If a 6-year-old child’s vision is 4.9 in both eyes, he/she may have a relatively delayed visual development, and close observation is usually sufficient, and his/her vision may gradually develop normally; if it does not return to normal, or even if his/her vision declines, he/she needs to undergo timely visual acuity, optometry, and funduscopic examination to determine the cause of the decline in vision. It is recommended to let children participate in outdoor sports more often, see distant objects more often, etc. If refractive error occurs, it should be corrected in a timely manner in a regular hospital.