Adipose-derived Mesenchymal stem cells have emerged as an attractive alternative source of cell therapy. While radiation therapy is an important application for head and neck cancer, the effect of adipose-derived mesenchymal stem cells on irradiated bone marrow-derived Mesenchymal stem cells is still unclear. Herein, we explored how clinical total radiation dose affect gene expression related with differentiation on murine bone marrow-derived mesenchymal stem cells and how murine adipose-derived mesenchymal stem cells affect irradiated murine bone marrow-derived mesenchymal stem cells. The clinical total radiation dose upregulates osterix mRNA expression. Moreover, adiposederived mesenchymal stem cells dramatically promoted the upregulation of osterix mRNA expression whereas inhibited NFATc1 mRNA expression. Taken as a whole, irradiated bone marrow-derived mesenchymal stem cells co-cultured with adipose-derived mesenchymal stem cells may exhibit osteogenic property.