Dry cough for two months needs close attention, mainly considering infectious diseases of respiratory tract and allergic diseases. Infectious diseases include tuberculosis infection, mycoplasma infection, etc. Tuberculosis infection has symptoms such as cough, little sputum, hot flashes, night sweats, even blood in sputum, and wasting, etc. Chest CT can assist in the diagnosis. If necessary, bronchial fiberscopy can be performed and alveolar lavage fluid can be given to check for antacid bacillus staining. If positive, chronic cough caused by tuberculosis needs to be considered. If imaging and fibrinoscopy are negative, that is, both tests are normal, further investigation is needed to see if the patient’s dry cough is caused by respiratory allergy. A bronchial provocation test, exhaled nitric oxide, and allergen testing can be given to find out if the patient has chronic inflammation in the airways that is causing the recurrent dry cough. If the imaging test is mostly negative, repeated anti-infection treatment should not be given at this time. Hormones, leukotriene receptor antagonists and antihistamines should be given for anti-inflammatory, anti-allergic and cough suppressant treatment to relieve dry cough as soon as possible.