objective:to observe the therapeutic effects of human fetal liver mesenchymal stem cells (hflmscs) induced by tat－pdx1 protein when transplanted into nod/scid diabetic mice. Methods:the hflmscs which were isolated and purified from fetal liver by adherent method,were induced to differentiate into islet β cells by tat－pdx1 protein. Nod/scid mice models of diabetes mellitus were established by injecting stz. The cells induced by tat－pdx1 protein were transplanted into left renal capsule,the blood glucose of diabetic nod/scid mice was detected. Results:the hflmscs induced by tat－pdx1 protein were expressed the mark of insulin in vitro. The level of mice blood glucose was degraded when the cells were transplanted into left renal capsule and was increased again when the left renal was excised. Conclusion:the hflmscs induced by tat－pdx1 protein can effectively reduce the level of nod/scid mice blood glucose. In the future,they will be the seed cells to treat diabetes mellitus.