Recent studies have shown that tumor microenvironment （TME） is significantly different from normal tissues， such as the change of abnormal enzyme expression， hypoxia， pH and so on. TME is closely related to the induced proliferation of tumor cells， angiogenesis， immune escape and the production of multidrug resistance. Cancer associated fibroblasts （CAFs） are the main stromal cell types in the TME. A variety of cytokines secreted by CAFs play an important role in tumor growth， invasion and metastasis. Understanding the role and mechanism of CAFs in the development of breast cancer is expected to provide a new target for improving the prognosis of breast cancer patients.