Based on the method of philology, this paper preliminarily combed the source theory of fire therapy through studying ancient medical works, and summarized as roasting, burning, smoking, ironing, warm acupuncture, fire needle, moxibustion and branding 8 ways. The fire therapy was explained by philological research. Literally, this paper pointed above its operation methods and explored its action mechanisms and symptoms. This paper also analyzed the development process of the therapy and the mutual relationship. The characteristics of the action and the analysis of the relationship are helpful to the inheritance and innovation of fire therapy.