The causes of persistent cough in children are as follows: 1, infection, is its most important cause, mainly manifested as wet cough, cough and accompanied by coughing up sputum; 2, bronchopneumonia or bronchitis, the patient’s cough after treatment of re-infection; 3, the patient in the formal treatment of high airway response, can be taken by means of nebulization and other means of treatment; 4, foreign body, in the diagnosis of the clear after the ciliophoroscopy can be taken out of the foreign body.5, allergy or Persistent exposure to allergens. 6, Cough variant asthma. The above are the main causes of persistent cough in children, but the most important cause of cough is infection, especially wet cough, especially without formal treatment, need to be vigilant.