Under normal circumstances, a six-year-old child should have a visual acuity of about 0.8. If your child’s vision is below this value, you may want to consider whether your child has a refractive error or an eye disease. 1. Refractive error: This may be due to unhealthy eye habits such as reading too close to books, excessive use of electronic devices, and reading in the dark. If either parent has high myopia, the child may also be genetically predisposed to myopia or prone to myopia, resulting in a visual acuity of less than 0.8. 2. Diseases: Eye diseases such as congenital cataracts, congenital amblyopia, intraocular hemorrhage, etc. may also lead to low vision, resulting in visual acuity of less than 0.8, which is usually still low after correction, and the visual impairment may worsen over time. If your child’s vision is abnormal, it is recommended that you seek prompt medical attention for definitive diagnosis and treatment to avoid aggravating the visual impairment.