Objective To investigate the curative effects of stereotaxic intracerebral transplantation of embryonic neural stem cells cultured in vitro on traumatic brain injury(TBI) in rats.Methods The embryonic neural stem cells were cultured in vitro.The models of TBI were made in the rats by Feenly et al method.The neural stem cells were stereotaxically transplantated into the brain in the rats with TBI 24 hours after TBI.The neurological defect scores were determined 24 hours before TBI and 24 hours,1 week and 2 weeks after TBI.Results The neurological defect scores were significantly lower in the transplantation group than those in the control group 1 and 2 weeks after TBI(P0.05).The number of neurons in the transplantation group was higher than that in the control group(P0.01).Conclusion The Neural stem cells transplanted into the injured cverebral tissues may survive,proliferate,differentiate,and improve the neurological function in the rats with TBI.