Abstract: This paper introduces the clinical experience of Professor CAI Wanru, a national master of Chinese medicine in Zhejiang province, in treating cough due to corona virus disease 2019 (COVID-19). Professor CAI holds that the cough due to COVID-19 belongs to the category of externally-contactive pathogenic qi. At first, the pathogenic qi invades upward, and affects the lung first, leading to the lung failing to diffuse and govern descent,the lung qi congestion,and cough due to the ascending counterflow of lung qi; the disease location lies in the lung, and the lung meridian is injured, which may easily transmiss the disease to the spleen or reversly to the kidney. The treatment should pay attention to syndrome differentiation,and it is advocated to treat by dispelling wind and stopping cough,diffussing the lung and relieving panting,and boosting qi and nourishing yin.