Abstract： By studying the discussion of lumbago in ZHU Danxi's related works and the existing research results， this paper analyzes and summarizes the theory of ZHU Danxi in treating lumbago and characteristics of his clinical prescriptions. In the syndrome differentiation and treatment of lumbago，ZHU Danxi attached great importance to the role of pulse manifestation，and believed that the liver，spleen and kidney， especially the kidney， are closely related to lumbago. In his treatment of lumbago， he selected different prescriptions according to different etiology，and used them cleverly and flexibly，with significant curative effect.