Children with yellow nasal discharge symptoms suggest the presence of bacterial infection, which can be seen in the upper respiratory tract infection, acute sinusitis. 1. Upper respiratory tract infection: upper respiratory tract infection is caused by viral infections, when combined with bacterial infections, the phenomenon of yellow pus runny nose can occur, accompanied by nasal congestion, sneezing, fever, cough and so on. 2. Acute sinusitis: children suffering from acute sinusitis, can also appear to flow sticky yellow pus nasal mucus, also accompanied by nasal congestion, fever, headache and other discomforts. Children with yellow nasal discharge may have other reasons, need to clarify the cause of the disease, active treatment. If it is prolonged, the nasal secretions should be actively drained to avoid blockage and secondary infection.