By studying the theory of properties and tastes and relevant literatures of Ye Tianshi and Wu Jutong,two TCM doctors specializing in treating epidemic febrile diseases,the author explores and summarizes the specific application rules of epidemic febrile diseases in the syndrome differentiation of ‘Wei(defensive phase),qi(qi phase),ying(nutrient phase),xue(blood phase)’ and ‘Sanjiao’. This paper concludes that the development of the theory of properties and tastes is closely related to its special syndrome differentiation system. In comparison with the syndrome differentiation of ‘wei,qi,ying,xue’ and ‘Sanjiao’ which are characterized by mixed syndromes with distinct levels and a wide coverage,the theory of properties and tastes is more flexible and practical than that of dominator and subordinate in application of Chinese medicine. At the same time,it is pointed out that the application of the theory of properties and tastes to the treatment of miscellaneous diseases and internal injuries under the guidance of the syndrome differentiation system of epidemic febrile diseases,has special clinical advantages and significance in modern TCM.