The mammary gland is the most frequently occurring organ of benign and malignant tumors in women, and there is a close relationship between the prevalence of internal organs and the physiology and pathology of the breast. Chinese medicine believes that the liver stores blood and is the main excretory, which is crucial for women’s menstruation, childbirth and milk excretion. The occurrence of breast diseases has a close relationship with liver qi stagnation. Melancholy injures the liver, and contemplation injures the spleen. Emotional disorders, the long depression injury to the liver, or mental stimulation, irritability, resulting in liver qi stagnation, qi stagnation in the breast, meridian obstruction, not through the pain, resulting in breast swelling and pain, liver qi depression and heat, heat burning yin, stagnation of blood clotting of breast lumps and pain, and further can occur in a variety of benign and malignant diseases. Therefore, dredging the liver and regulating qi is an important rule in the treatment of breast diseases, and regulating emotions is crucial for the recovery of breast diseases.