Breast cancer is a major disease affecting women's health. The tumor microenvironment is a complex and dynamically changing group of cells and non-cellular components involved in the process of tumor progression. At present, more and more evidence indicates that exosomes in the breast cancer microenvironment can participate in the occurrence, development and prognosis of breast cancer by regulating the proliferation, epithelial mesenchymal transformation, metabolism, stemness and drug resistance of breast cancer cells. Starting with the structure of the human breast, this paper summarizes a series of advances in knowledge about exosomes in the breast cancer microenvironment, focusing on their regulatory role in breast cancer and their molecular mechanisms, thus providing new ideas for the diagnosis and treatment of breast cancer.

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