Abstract： Professor PANG Dexiang， a famous provincial traditional Chinese medicine physician in Zhejiang Province，has been engaged in Chinese medicine clinic for 50 years，accumulated rich experience in diagnosis and treatment， and formed his own unique system of differentiation and treatment. Breast cancer is the most common malignant tumor in women. Professor PANG Dexiang proposed to treat breast cancer from the liver according to his long- term clinical experience， and found an effective formula， namely Sanjie Xiaoyao Powder， which has a significant clinical effect. The authors expounded the theoretical basis for the treatment of breast cancer from the liver，the clinical application of Sanjie Xiaoyao Powder， and the syndrome- based modification， and extracted two proven cases during their clinical practice and study for the readers.