During his long-term clinical practice，master of traditional Chiense medicine(TCM)and Professor LYU Renhe creatively puts forward “six diagnosis and treatment principles”，which includes treatment according to diseases，treatment according to disease differentiation，treatment according to disease differentiation and stage，treatment according to symdromes，treatment according to symptom differentiation，as well as combination of treatment according to disease differentiation and treatment according to syndrome differentiation．Such principles run through diagnosis and treatment of diseases by Professor LYU Renhe.With the ability of clearing heat and promoting dieresis，Artemisia capillaris Thunb is one of the common herbal medicine used by Professor LYU.Based on Professor LYU Renhe's “six diagnosis and treatment principles” clinical thinking，this paper explores Professor LYU's experience in clinical application of Artemisia capillaris Thunb and provides new ideas for clinical practice.