Redness of the lower eyelid in children may be caused by allergy, conjunctivitis, erysipelas and so on. 1. Allergy: mainly due to the patient’s contact with allergens, the body through skin contact, ingestion, inhalation and other ways of exposure to allergens, will lead to children’s lower eyelid redness. 2. Conjunctivitis: when subjected to microbial infections, external stimuli, physical and chemical stimuli, inflammation of neighboring tissues or systemic diseases and other factors, will lead to children’s lower eyelid redness, most often manifested in the eyes of foreign body sensation, burning sensation, increased secretion and other discomforts, and accompanied by photophobia, tearing and other symptoms. 3. Staphylococcus: staphylococcus, especially staphylococcus aureus infection, resulting in children’s lower eyelids red, mainly manifested as red, swollen, hot and painful, tearing, photophobia and other symptoms. Parents are advised to bring their children to the hospital in time, under the diagnosis of the doctor, according to the specific condition of the child, to take targeted treatment.