Masking is a common treatment for amblyopia. However, many amblyopic children feel uncomfortable with it because they think it will affect their aesthetics, and therefore have strong resistance or fear. Some amblyopic children may even remove it secretly when their parents are not looking. This is very detrimental to amblyopia treatment. Of course, when amblyopia treatment is carried out to a certain extent, it is possible to remove the mask, but this also depends on whether the time is ripe. The reason why it is important to see the right time for amblyopia treatment before covering is that it can lead to repeated ambly and increase the chance of recurrence in the future. The worrying thing is that many parents think they can remove the mask when they hear that their child’s amblyopia has been clinically cured. It is important to emphasize that a clinical cure is not the same as a complete cure. The following criteria can be used as a reference for the timing of removal of the mask. However, in clinical practice, patients should listen to the physician’s guidance on when it is appropriate to remove the mask. 1. The visual acuity of the poor eye reaches its optimal level. The visual acuity mentioned here refers to the corrected visual acuity. As for the optimal level, it should be decided according to the specific situation of the amblyopic patient. 2. The visual acuity of the poor eye reaches, exceeds, or is close to the level of the healthy eye. This situation is more common among patients with binocular amblyopia or amblyopia in one eye more than the other. It is important to emphasize that it is important to balance the rehabilitation progress of both eyes when they have different levels of amblyopia. 3. In severe amblyopia in one eye, the masking period should be extended. Visual acuity is not the only criterion for considering the degree of amblyopia. Because the poor eye of a person with severe amblyopia has a weak innate advantage and lacks the strong capital to compete with the healthy eye, it needs to accumulate more strength to resist the competition of both eyes after opening the mask. 4. Having simultaneous vision ability. The simultaneous vision ability of amblyopic patients needs to be examined with the help of a simultaneous vision machine. Determining whether the patient has monocular suppression and whether the poor eye has central suppression through the examination is an important criterion to determine the timing of their de-masking.