Microphthalmos is a congenital eyelid abnormality that is autosomal dominant and is characterized by ptosis, microphthalmos, reverse canthus, and widening of the medial canthus, as well as mental retardation, developmental delay, and heart defects in some cases. The timing of surgery is controversial. Early surgery can better prevent form deprivation amblyopia, but because the child is too young and has immature tissue development, premature surgery often results in postoperative recurrence and inadequate correction, thus affecting the outcome of the surgery. Late surgery can achieve more stable surgical results, but it can affect the development of visual function. Therefore, it is necessary to consider the anatomical and physiological development of the patient and the extent of its impact on visual function. Lid opening can be performed around the age of 3 years, or earlier than 2 years of age in cases of severe ptosis and severe reverse canthus.