RESUMEN
Objective]Study on the etiology and pathogenesis of exogenous diseases of Treatise on Seasonal Diseases. [Methods]Using the history of Traditional Chinese Medicine method, traditional Chinese medicine philological method and theoretical analysis method.[Results]The exogenous diseases were divided into instant diseases and incubated diseases by Lei Feng. He pointed out that the pathogenic evils hidden in the weak place. Pathogenic evils lurk in the internal and external causes. Different pathogenic evils are hidden in different position. There are three different forms of the attack of incubated disease. [Conclusion]Lei Feng's study on the etiology and pathogenesis of exogenous disease, especially the attack of incubated disease, has certain reference value for today's treatment of the Traditional Chinese Medicine of exogenous diseases.