Objective To explore the mechanism of quercetin against the toxicity of amyloid β(Aβ)to neuroblastoma cell SK -N -SH.Methods In the experiment,SK -N -SH cells were divided to four groups,control group,Aβgroup,Aβ+quercetin group and quercetin group,and treated for 72h.The proliferation of cells,the concen-trations of reactive oxygen species (ROS)and glutathione (GSH)in cells were determined.Results Compared with the control group,Aβ[AβgrouP =(50.6 ±2.5)]could significantly suppress the proliferation of neuroblastoma cells (P =0.000).However,Aβgroup added with quercetin[Aβ+quercetin =(88.0 ±9.1)]showed decreased cellular toxicity induced by Aβ(P =0.001).Additionally,there was no significant difference between the control group and quercetin group.Likely,the concentration of ROS increased in Aβgroup (523.3 ±22.5 ),which was higher than (190.3 ±25.7)in the control group and (224.0 ±56.0)in quercetin group (P =0.000).At last,quercetin could increase GSH level in SK -N -SH cells and higher than Aβgroup[(3.0 ±0.2),P =0.004]and Aβ+quercetin [(5.6 ±1.1),P =0.008].Conclusion Quercetin could attenuate the suppression of proliferation of SK -N -SH cells induced by Aβ,that might be though increased concentration of GSH and decreased level of ROS.These data suggested that quercetin has clinical potentials in neurology.