Abstract： Through reviewing ancient medical books， this paper summarized the history of toxic pathogen theory，including its proposal，development and formation. The paper aimed to comprehensively understand theoretical connotation and clinical basis of the theory， so as to enrich the academic connotation of different schools in Chinese medicine， and provide valuable historical data for many Chinese medicine therapies， especially the attacking- toxin therapy. The author believes that the toxic pathogen theory is a very important academic viewpoint to explain etiology and pathogenesis in Chinese medicine，and a comprehensive theory that is in line with objective reality. The theory will have positive effect on guiding the study of cold damage and warm diseases and the study of pathogenic microorganism in modern medicine， and provide theoretical basis for the development of attacking-toxin therapy of Chinese medicine.