Congenital cataracts have different clinical manifestations, and the degree of vision loss is related to the location and extent of lens clouding. At present, congenital cataract is still mainly treated by surgery, and mastering the appropriate timing of surgery is an important aspect to decide whether the child can recover his vision. In general, the following principles should be mastered: 1. For those who have complete cataract in both eyes after birth and whose retina is not stimulated normally, which seriously affects the development of visual function, surgery should be performed as early as possible. Generally, surgery should be performed within 1 to 2 months after birth, and no later than 6 months. The other eye should be operated within 1 week after the first eye surgery, and the postoperative monocular masking should not exceed 1 week to prevent the occurrence of form deprivation amblyopia due to monocular masking after surgery. 2. Incomplete cataract in both eyes: If the visual acuity of both eyes is lower than 0.1 and the fundus cannot be seen, early surgery should also be strived for. 3.For monocular congenital cataract with lens clouding in the pupil area or bilateral visual acuity below 0.3, surgery should be performed as early as possible at the age of 2 to 3 years. 4. For limited lens clouding, the surgery can be postponed to 4 to 5 years of age if it does not affect play and the visual acuity is above 0.3, but not later than 6 years of age, otherwise it may cause irreversible amblyopia. 5. Patients with rubella syndrome should not undergo surgery prematurely, because in the early post-infection period, the rubella virus is still present in the lens, which can cause iritis due to virus release during surgery, and surgery is generally advocated at the age of 2 to 4 years. In conclusion, the importance of early surgery must be emphasized, and corrective glasses should be worn early after surgery to avoid amblyopia, followed by second-stage IOL implantation according to the patient’s ocular development and visual acuity.