In the light of obscure conception of Ashi points in the circle of acupuncture and moxibustion at present, this article tries to clarify the origin and definition of Ashi points by textual research of literatures. It is put forward that Ashi points are not the same with "tender spot" and "Buding point, Tianying point", but are some special responding points, including regular points and extra points, when the organism is ill. When these points are pressed the organism will be comfortable or painful. And the definition, location and clinical location method of Ashi points are proposed.