It is proposed that a coronavirus disease 2019（COVID-19） is caused by the epidemic cold pathogen

and has characteristics of both toxicity and cold pathogen. The enset include immediate onset of the diseases being caused by exogenous disease

onset by exogenous disease and relapse after recovery. The syndrome characteristics of concurrent disease of Taiyang and Shaoyang

concurrent disease of Shaoyang and Yangming

and concurrent on the same disease of three yang

pathogen toxicity transforming into heat and congestion and excessiveness of heat and toxin

cold pathogen damaging yang are elaborated. Clinically

expelling pathogen and detoxification method is used based on Jinchai Decoction（金柴饮） to eliminate toxicity from the superficies

ventilating lung for benefiting qi

supporting the healthy energy and dispelling pathogen

stopping the patients′ condition

to expelling pathogen and toxicity. The author also cites examples of typical cases of patients with COVID-19 treated with the method of expelling pathogen and detoxification

in order to enrich the theory and practice of traditional Chinese medicine（TCM） prevention and treatment of epidemics

and to improve the clinical efficacy of TCM in the treatment of COVID-19.