Abstract: Mesenchymal stem cells are a kind of adult stem cells characterized by the ability to self-renew and differentiate into multiple cell types. Recently, more attention has been paid to the immunomodulation and regenerative capacities of mesenchymal stem cells (MSCs). Macrophages are essential components of innate immunity. Researches have illustrated that mesenchymal stem cells are able to regulate the phenotype and function of macrophages, and the alteration of macrophages plays a pivotal role in controlling inflammation and facilitating tissue repair. In this review, the mechanism of the regulatory effect of MSCs on macrophages are analyzed and summarized, which may provide a new insight into the clinical application of mesenchymal stem cells.