Objective To explore the short-term curative effect and safety of autologous bone marrow mesenchymal stem cells transplantation in patients with primary brain stem injury.Methods Fifty-four cases with primary brain stem injury were hospitalized during Jul.2007 to Jul.2010 at Liaocheng Brain Hospital,Shandong Province.All cases were randomized into transplantation group( n =30)or control group( n =24 ).The transplantation group was treated with autologous bone marrow mesenchymal stem cell transplantation by subarachnoid space injection (n =30).The control group were selected from primary brain stem injury patients without stem cell transplantation who were hospitalized at the same period with patients from the transplantation group.Respectively,National Institutes of Health Stroke Scale (NIHSS) score was employed to evaluate the condition of patients in the two groups one month after treatment,and Glasgow Outcome Scale (GOS) score was used to evaluate curative effects of the two groups at sixth months after treatment.Meanwhile,some other parameters were observed,including blood routine,clotting mechanisms,biochemical items and tumor markers.Results There was significant difference between the transplantation group and the control group in N IHSS score at one month after treatment [ ( 10.86 ± 7.48) vs.( 18.26 ± 8.74),t =2.681,P ＜ 0.05 ].GOS score was significantly different( Z =2.306,P ＜ 0.05 ) between the transplantation group and the control group at sixth month after transplantation.There was no significant difference between the two groups in the blood examination results during the followed-up period.Conclusion Autologous bone marrow mesenchymal stem cells transplantation is confirmed to be an effective and safe therapy in patients with primary brain stem injury in the short-term.Further evaluation still needs for its long-term efficacy on primary brain stem injury