Infants with eye bags may be caused by heredity, trauma, acute glomerulonephritis, nephrotic syndrome and other reasons. 1. Heredity: Infants with bags under the eyes may be caused by congenital heredity leading to hypertrophy of the orbicularis oculi muscle. 2. Trauma: If there is a history of trauma to the baby’s eyes, resulting in orbicularis or orbital septum injury, it will easily cause orbital septum fat to protrude with the weak skin, and then also form bags under the eyes. 3. Acute glomerulonephritis: this disease is mainly caused by β-hemolytic streptococcal infection, which often occurs after tonsillitis, scarlet fever and other diseases, and other common pathogens are bacteria, viruses, parasites and so on. Because the children will have eyelid edema, so there can be bags under the eyes, there will be hematuria, proteinuria and other symptoms. 4. Nephrotic syndrome: the cause of this disease is not yet completely clear, it is thought to be related to genetics, infection, immunity and other factors, usually caused by glomerular injury. The children will have symptoms such as hypoproteinemia, hyperlipidemia, edema, weight gain, etc. Most of the children have eyelid edema, which is manifested as having bags under the eyes. Infants with bags under the eyes are advised to go to the hospital for a complete examination to determine the exact cause.