新型冠状病毒肺炎是一种烈性传染病，属中医学“疫病”的范畴，广义“伤寒”包括传染病，不同医家对其病性认识有所不同，清肺排毒汤作为中医药治疗的首选方案，将从该方出发，以方测证，并从六经辨证的角度分析新型冠状病毒肺炎的发生发展传变的过程及其辨证治疗，挖掘经方对新冠肺炎的临床价值。 湿邪是导致新型冠状病毒肺炎的重要致病因素，病位主要在肺和脾，重点分析湿邪尤其是寒湿邪气的治疗方法，清肺排毒汤辛温配辛凉，宣肺平喘，解毒化湿，为寒湿犯肺困脾所致疾病提供治疗借鉴。

COVID-19 is a severe infectious disease， which belongs to the category of epidemic in traditional Chinese medicine. The extensive term “exogenous cold diseases” includes infectious diseases， on which different doctors have different understandings. Qingfei Paidu Decoction is the first choice for Chinese medicine treatment of COVID-19. This paper starts from this prescription and deduces the syndrome with the prescription， and then the process of the occurrence， development and transmission of COVID-19 and its treatment based on syndrome differentiation are analyzed from the perspective of syndrome differentiation of the six channels. Damp pathogen is an important pathogenic factor of COVID-19. The disease location is mainly in the lungs and the spleen. The focus of this paper is on the treatment of damp pathogen， especially the cold and damp pathogenic factors. Qingfei Paidu Decoction is combined with pungent warm natured drugs and pungent cool natured drugs， to disperse lung qi and relieve asthma， and to remove toxicity and dampness. This paper tries to provide a reference for the treatment of diseases caused by cold and dampness invading the lung and trapping the spleen.