Yellow nasal mucus is a sign of bacterial infection, sinusitis and late stage of cold. If clear nasal discharge turns into yellow nasal discharge or early yellow nasal discharge is more frequent during the cold, bacterial infection is considered, and it is best to treat it as soon as possible with antibacterial agents, such as roxithromycin or azithromycin, together with cetirizine to relieve congestion and edema of nasal mucosa to achieve the efficacy of treating runny nose. If the runny yellow nose is more than half a month, the effect of common cold medicine is not good, and accompanied by obvious headache symptoms, consider sinusitis. After going to ENT department to confirm the diagnosis with rhinoscopy and film, you can use antibacterial, physiological sea salt water to rinse the nasal cavity and anti-allergy treatment. After a week of poor results, further treatment is needed. Most of the children can improve significantly after about two weeks of continuous treatment. If the runny nose is less, the nasal discharge is clear and yellow, which is the manifestation of late stage of cold, the symptoms can be relieved without treatment or by rinsing the nasal cavity with physiological sea salt water. Pay more attention to eating foods containing vitamin C, such as oranges, kiwi, tomatoes and so on, which are good for disease recovery. So the causes of yellow nasal discharge are different and so is the treatment. Identifying the causes and treating the symptoms can relieve the symptoms of yellow nasal discharge in children.