Abstract: This study aims to investigate the cytoprotective mechanism of torularhodin against oxidative stress.PC12 cells were randomly divided into control group and model group( 200 μmol/L H₂O₂), lycopene group(20 μmol/L lycopene+200 μmol/L H₂O₂,positive control group) and torularhodin groups(1 μmol/L torularhodin+200 μmol/L H₂O₂,2 μmol/L torularhodin+200 μmol/L H₂O₂ and 3 μmol/L torularhodin+200 μmol/L H₂O₂). The changes of PC12 cell morphology were observed,while the apoptosis rate of cell,the activity of Caspase-3 and expressions of pro-apoptotic protein Bax and anti-apoptotic protein Bcl-2 were also detected. Results showed that 3 μmol/L torularhodin could maintain the original shape of cell,reduce 11.6% apoptosis rate(p<0.05) and inhibit 62.92% Caspase-3 activity(p<0.01),comparing with the model group. Further study demonstrated that torularhodin could down-regulate the expression of Bax(p<0.01) and up-regulate the expression of Bcl-2(p<0.01),which thereby prevented chain reaction of apoptosis and protected cells from oxidative stress. In a word,torularhodin could effectively protect cells against oxidative stress,by mechanisms which probably involves the inhibition of Caspase-3 activity and adjustment of Bax,Bcl-2 expression in dose-dependent manner.