The causes of yellow-green secretion on children’s underwear include physiological and pathological reasons, pathological reasons are mainly vaginitis, penile and so on, can be treated by antibiotic drugs. 1. Physiological factors: under normal circumstances, children will normally secrete some secretions, if the child does not do a good job of cleaning and sanitation in time after urinating or defecating, it will lead to part of the excreta left in the underwear. At this time, you need to change your underwear regularly and pay attention to your child’s personal hygiene. 2. Pathological factors: young girls because of anatomical characteristics, bad habits and other pathogens that can easily lead to vaginal infections, mainly manifested as vulvar redness, swelling and itching, purulent secretions increase. For bacterial infection, amoxicillin can be used orally, and mycoplasma infection can be used erythromycin. If the prepuce of young children is not treated in time, the foreskin scale will stimulate the urethral opening and produce purulent secretions. If it causes inflammation, it can be treated with cephalosporin antibiotics. It is recommended to consult with the hospital in time to clarify the cause of the disease and target the treatment.