【Abstract】 Mesenchymal stem cells (MSCs) are adult stem cells with selfreplication and multipotential differentiation, which can differentiate into bone, cartilage, fat, endothelial and other cells under specific induction conditions in vivoor in vitro. MSCs have low immunogenicity and strong immunomodulatory effect. Based on the diversity of biological characteristics of MSCs, the current research on MSCs involves antiinflammatory therapy, tissue repair and regeneration, graftversushost disease (GVHD), autoimmune diseases and other aspects, which has a broad clinical application prospect. In this paper, the biological characteristics of MSCs are reviewed.