Under normal circumstances, the normal naked eye vision of a six-year-old child should be maintained between 0.8 and 1.0, which is the normal visual acuity range. If the child’s visual acuity is below normal, for example, 0.6 or below, after a vision check, certain eye diseases such as refractive error, amblyopia, congenital fundus disease, and congenital cataract may be present. In this case, you should take your child to the hospital for a detailed eye examination, including fundus examination, intraocular pressure examination, and optometry examination. Through these examinations, we can initially determine the specific cause of the child’s vision loss and provide symptomatic treatment according to the specific condition. If detected in time, most of the diseases can be treated. If it is refractive error, glasses can be worn; amblyopia requires amblyopia treatment and training; fundus disease or congenital cataracts may require surgery.