Abstract: Objective To investigate the therapeutic effects of rat bone marrow-derived mesenchymal stem cells(MSCs) transplantation into the corpus striatum of the 6-OHDA injection side of the Parkinson's disease(PD) rat models. Methods The BrdU labeled MSCs were transplanted into the corpus striatum of the 6-OHDA injected side of 6 model rats. Before MSCs transplantation and 8 weeks later, the ethological changes of PD rats were detected. After 2 days the concentrations of N-acetylaspartate(NAA), Choline(Cho) and Creatine(Cr) were calculated by 1H-MRS. Relative concentrations of NAA/Cr and Cho/Cr were recorded. The expression characteristics of tyrosine hydroxylase(TH) in substantia nigra compacta(SNc) were checked and the migration of the transplanted cells were observed using immunocytochemical and immunofluorescent methods. Results The rotational behaviors of PD rats improved, and there were statistical differences in the survival TH positive cells in SNc after the transplantion of BrdU labeled MSCs. The BrdU positive cells scattered in the transplantation side of the brain and showed GFAP positive and Map positive partly. Compared with before transplantation, The NAA/Cr radio of the 6-OHDA injected side of striatum was increased (P<0.05) and the Cho/Cr radio was decreased(P<0.05). Conclusion The transplanted MSCs can survive in the PD rat brain and has the therapeutic effect to PD.