Since the discovery of COVID-19，it has been characterized by rapid onset，rapid transmission and obvious infectivity，which belongs to the category of epidemic diseases studied in traditional Chinese medicine. At present，traditional Chinese medicine has demonstrated promising results in the treatment of COVID-19. Since the pathogenesis and syndrome of COVID-19 are roughly consistent with febrile disease，it can be analyzed from the perspective of febrile disease from the view of traditional Chinese medicine. As is well known，Wei-Qi-Ying-Xue is an important theoretical basis in febrile disease. The law of transmission and syndrome characteristics can be explained through the syndrome differentiation of Wei-Qi-Ying-Xue，which brings more possibilities for the diagnosis and treatment of COVID-19. Reviewed the evolution history of syndrome differentiation of Wei-Qi-Ying-Xue，based on TREATISE ON EPIDEMIC FEBRILE DISEASES，epidemic febrile disease from light to heavy symptoms was divided into four stages，and the pathogenesis characteristics of COVID-19 were analyzed. Combined with syndrome differentiation of Wei-Qi-Ying-Xue，this review interpreted the change law of COVID-19. The immune status in different stages of COVID-19 was associated with the syndrome characteristics of four stages of Wei-Qi-Ying-Xue. This review also summarized the significance of application of Wei-Qi-Ying-Xue in the treatment of COVID-19，combining traditional Chinese and western medicine，so as to provide more references for the diagnosis and treatment of COVID-19.