The optimal age for corrective surgery for strabismus is between 2 and 5 years old, as it varies depending on the type of strabismus and the development of binocular vision. In the case of internal strabismus, if conservative treatment fails to correct it, surgery is recommended as early as possible because internal strabismus is more damaging to the visual function of both eyes. In the case of external strabismus, most of the cases are intermittent, and the damage to visual function is relatively small compared to internal strabismus. Moreover, even if the surgery is performed at an older age, some patients can also recover their visual function. Therefore, the age of correction can be considered to be appropriately relaxed. If strabismus exists, it is recommended to go to the hospital for examination in time and follow the doctor’s instructions for treatment, so as not to delay the condition.