Abstract: Objective To investigate the experimental condition and mechanism of differentiation of human umbilical cord blood derived mesenchymal stem cells(hUCB-MSC)into neuron-like cells induced by recombined human epidermal growth factor (rhEGF) and taurine in vitro.Methods hUCB-MSC were primary cultured in Dulbecco's modified Eagle's medium/F-12 (DMEM/F-12)which supplemented with 105U/L penicillin G,100 mg/L streptomycin sulfate,10% fetal bovine serum (FBS),5% autologous plasma,4 mmol L-glutamine,30 ng/ml rhEGF.The DMEM/F-12 medium was replaced by taurine medium after 3 passages.The expression of surface antigen CD90.CD29.CD34.CD44 and CD45 were detected by flow cytometry;the expression of neuron specific enolase,rhodopsin and nestin were investigated by immunoeytochemistry.The statistical method was chi square test.Results Morphologically similar to bonemarrow MSC,hUCB-MSC became attached cells after the first 5 to 7 days in culture,and reached 80% to 90% confluent after 3 to 4 weeks.Growth accelerated after passage,hUCB-MSC were positive for CD29,CD44 and CD90 but negative for CD34 and CD45.After taurine induction,2515/3120 cells expressed NSE,1168/3175 cells expressed rhodopsin and 903/3050 cells expressed nestin while only 234/2965 cells expressed NSE in the control group (P<0.01).Conclusion rhEGF and taurine can induce hUCB-MSC differentiating into neuron-like or rhodopsin positive cells.