Most of the babies’ large and small eyes are caused by physiological reasons, such as long-term side-lying sleep, imperfect development of the levator muscle, etc. With the development of babies, most of them can recover. A few babies have pathological causes, such as ptosis, intraocular tumors, etc. Most of them cannot be cured by themselves and need surgical treatment. Prolonged side-lying sleep may lead to large and small eyes, usually the symptoms are relatively mild, as long as you change the child’s sleep position, it will gradually recover. For babies with underdeveloped levator muscle, as they grow and develop, the upper eyelid will gradually become fixed and the large and small eyes will disappear. If the baby has problems with the nerves or muscles of the levator muscle, which is manifested as ptosis, it is recommended to have surgery as soon as possible if the size of the eye is obvious, otherwise the development of vision may be affected, and even amblyopia may occur. If the baby has intraocular tumors, such as retinoblastoma, which may cause eyeball protrusion and large and small eyes, once diagnosed, timely surgical treatment is recommended. In conclusion, when the baby has a large or small eye, it is recommended to consult ophthalmology and pediatric surgery in time to clarify the cause of the disease and take targeted treatment.