Amblyopia is visual development caused by monocular strabismus, uncorrected refractive aberration and high refractive error and form deprivation caused by monocular or binocular best corrected visual acuity below the corresponding age visual acuity, or binocular visual acuity difference of two lines or more. It is worth noting that the lower limits for different age reference values are: 3-5 years old: 0.5; ≥6 years old: 0.7 to 1.0. Parents should actively participate in routine eye examinations 42 days and 1 week after birth and before the child enters school. Children with low or abnormal vision should go to an ophthalmologist for a detailed examination as soon as possible, usually starting with a dilated eye exam in the ophthalmology department. Optometry for children, especially for the first time, is best done with dilated pupils. The purpose of dilating the pupil is to relax the ciliary muscle inside the eye, remove the eye’s own regulation, and make the eye completely relaxed. This allows the true refractive power of the child’s eyes to be determined. After the pupil returns to its normal size, the test is repeated once and the refractive state of the child’s eyes is accurately known based on the number of degrees twice. The prime time to treat amblyopia is before the age of four. The younger the child, the better the treatment effect, not only the shorter the course of treatment, but also the higher the cure rate. The older the child is, the worse the treatment effect will be. 12 years old and above, the developmental period of the visual system has passed, and most patients cannot obtain satisfactory treatment results. After adulthood, there is little hope of curing amblyopia. Early detection and treatment of amblyopia is important. Parents should teach their children to check their vision early to find out if they have poor vision or even amblyopia, so that they do not miss out on treatment and cause their children lifelong regrets. The most effective way to treat amblyopia is masking therapy —— to cover the eye with good vision and force the child to use the eye with poor vision. Many children are often uncooperative when it comes to treatment because the affected eye cannot see well, so the child will secretly remove the cover and use the good eye, or refuse to cover the good eye for fear of being ridiculed as a “one-eyed dragon”. Parents must clarify the necessity of amblyopia treatment, communicate with their children in a timely manner, and obtain their children’s cooperation through encouragement and rewards so that they can complete amblyopia treatment with quality and quantity. It is vital that the child has balanced vision in both eyes. If only one leg can walk and the other leg is lame, even if the lame leg is positioned correctly, the child cannot walk in a coordinated manner. Especially if a strabismic child has amblyopia, the amblyopia must be treated first. This is because strabismus surgery can bring the eyes into proper position, but the post-operative effect depends largely on whether the vision is balanced in both eyes. Follow-up visits should be reinforced during the masking period to prevent the occurrence of masked amblyopia. Especially when parents change the eye mask and open both eyes, if they find that the original strabismus eye continues to maintain gaze, it means that the visual acuity of the strabismus eye has exceeded that of the main eye, and should be reviewed immediately.