The relationship between taurine and aging of brain neural cells was studied by using primary human fetal brain neural cells cultured in serum-free medium. The results indicated that the activity of superoxide dismutase (SOD) was significantly higher in taurine added group than the control group cultured for 6, 9 and 15 days (P < 0.05). With different taurine levels, the SOD activities of 50 mg/L and 200 mg/L taurine groups were significantly higher than the control group cultured for 6 days (P < 0.05). After 3-day culture, the activity of glutathione peroxidase (GSH-Px) in the taurine added group was significantly higher than the control group (P < 0.05). The membrane lipid fluidity of neural cells decreased with time in control group, but was stable in the group treated with taurine. The fluidity was more stable in the groups treated with 50, 200 and 400 mg/L groups cultured for 6 days, compared with the control group (P < 0.05 or 0.01). The present study showed that taurine is necessary for maintaining membrane lipid fluidity of neural cells in proper levels, and plays an important role in postponing the aging process of brain neural cells.