Abstract: Mesenchymal stem cells (MSCs) are pluripotent stromal cells present in various tissues. Exosomes are intercellular communication carriers that can transfer bioactive molecules such as bioactive lipids, nucleic acids, and proteins between cells. Studies have shown that exosomes secreted by mesenchymal stem cells (MSC-EXO) are a major component of the tumor microenvironment and play an important role in the development, angiogenesis and metastasis of tumors. This review aimed to demonstrate the knowledge of mesenchymal stem cell-derived exosomes in cancer research and its mechanism of action on tumors and provides new ideas for the appropriate use of modified MSC-EXO as a strategy for cancer therapy in the future.