The specific reasons for coughing at night are as follows: 1. It is related to the environment, as the air temperature is low at night, people are generally more sensitive to cold air, which can trigger a cough. 2. The dust mites will come out of the quilt and pillow, and the inhalation of dust mites will cause coughing due to allergies. To sum up, these three are the reasons why you often cough at night.