The diagnosis of pediatric cough variant asthma is specifically as follows: 1. The onset of cough is greater than four weeks, with nearly a month of persistent cough, mainly dry, usually with little sputum, relatively pronounced in the early morning or at night, with relatively mild symptoms during the day; 2. The cough is not considered to be caused by infection for a long period of time, such as Mycoplasma pneumoniae infection, so the infection can first be ruled out by taking a chest X-ray or blood tests to rule out Infection; 3. Diagnostic treatment is effective, such as treatment with anti-asthma, such as budesonide inhalation, salbutamol or terbutaline inhalation, which can significantly relieve symptoms; 4. Other causes of chronic cough are excluded, such as tuberculosis, persistent mycoplasma pneumonia, and chronic pneumonia; 5. Relevant tests, such as a positive airway excitation test, or a daily variability of peak expiratory flow rate of 20% or more; 6. Relatives of the affected child, or The first or second degree relatives of the child have a history of allergy, such as grandparents with allergic rhinitis or asthma, which is also a diagnostic criterion. The first four items above are the necessary conditions for diagnosis.