Chemotherapy is an important method of treating breast cancer. Currently, the commonly used chemotherapy drugs bring a series of side effects while killing tumor cells, which leads to a decrease in the quality of survival during chemotherapy, and some patients are even unable to complete chemotherapy successfully. Therefore, it is important to ensure the efficacy of chemotherapy. At the same time, it becomes very important to effectively reduce the toxic side effects of chemotherapy. According to Chinese medicine, breast cancer is mainly caused by the deficiency of positive energy and external evil, resulting in the imbalance of yin and yang in the body and the disharmony of internal organs. Surgery and chemotherapy further injure the body’s vital energy. Insufficient positive qi leads to obstruction of the flow of qi and blood, and stagnation of qi leads to blood stasis. Therefore, spleen deficiency with blood stasis is a common clinical evidence during chemotherapy for breast cancer. In this formula, Astragalus membranaceus, Radix et Rhizoma Atractylodes Macrocephala, Poria and Rhizoma Polygonati are used to strengthen the spleen and benefit the qi; Salvia miltiorrhiza, Radix Panax Ginseng and Radix Angelicae Sinensis are used to tonify the blood and invigorate it; Pericarpium Citri Reticulatae and Radix Panax Notoginseng are used to calm the stomach and stop vomiting. The combination of all the drugs, together with the benefit of Qi and blood, and stomach to stop vomiting. Modern research has found that Astragalus can improve body immunity, increase macrophage phagocytosis, improve INK cell activity, induce interferon production, promote bone marrow hematopoietic function and promote the production, development and maturation of various types of blood cells. Atractylodes can correct the state of T-cell subpopulation distribution disorder. The Poria polysaccharide in Poria has tumor suppressive effect on a variety of tumors. In addition, chemotherapy can cause and aggravate patients’ blood hypercoagulability. The use of blood-activating drugs such as Salvia miltiorrhiza, Panax ginseng and Angelica sinensis can improve blood hypercoagulability and promote bone marrow hematopoietic function. Radix et Rhizoma can improve side effects such as vomiting. Our department prepares self-prepared Yi Qi and Blood Invigorating Tang (Astragalus, Radix et Rhizoma, Atractylodes Macrocephala, Salviae Miltiorrhizae, Panax Ginseng, Poria, Radix et Rhizoma, Radix Angelicae Sinensis, Radix Panax Notoginseng, Pericarpium Citri Reticulatae, Radix et Rhizoma Glycyrrhizae) Yi Qi and Blood Invigorating Tang can effectively improve the toxic side effects of chemotherapy in breast cancer patients with spleen deficiency and stasis, but please use it only after proper diagnosis and identification by specialist.