Coughing at night and not coughing during the day may be caused by pathologic factors such as cough variant asthma and cardiac insufficiency, or it may be due to environmental factors such as poor air circulation. 1. Cough variant asthma: it is a chronic airway inflammation mainly characterized by eosinophilic infiltration. The cough is usually paroxysmal, mostly seen at night, in addition to cold air, pollen, dust, respiratory infections, etc. are also triggering factors. 2. cardiac insufficiency: heart failure patients lying down at night pulmonary edema aggravation, there will also be night cough. However, nocturnal cough is not the main manifestation of cardiac insufficiency, the main clinical manifestation of cardiac insufficiency is dyspnea, and some patients will have cough symptoms. 3. Lack of air circulation: some cough patients will close the doors and windows when they sleep, resulting in indoor air circulation. During the period of illness, the throat and bronchial tubes are more sensitive than usual and are easily stimulated by the outside world. You can open the windows during the day to allow indoor and outdoor air circulation and relieve coughing symptoms. Patients who cough at night but not during the day should go to the hospital for further examination and diagnosis, to be able to further clarify the cause of the disease, and standardized treatment according to the doctor’s guidance.