Abstract： Objective： To discuss the mechanism of Shaoyao Gancao Oil(SGO) protecting pheochromocytoma(PC12) cells of rats from oxidative damage induced by hydrogen peroxide(H2O2). Methods：The PC12 cells were treated with 200 μmol/L H2O2 and established as the models with oxidative damage. The PC12 cells were divided into the control group，the model group(200 μmol/L H2O2)，the lowconcentration SGO group(1 μmol/L SGO+200 μmol/L H2O2) ， and the high-concentration SGO group (10 μmol/L SGO+200 μmol/L H2O2). After the treatment of the PC12 cells，the cell viability was detected by the method of CCK- 8； the activity of superoxide dismutase(SOD)， as well as the contents of malonic dialdehyde(MDA) and glutathione peroxidase(GSH- PX) of cells were detected by kits；the apoptosis ratio was detected by flow cytometry； the protein expressions of cleaved- caspase3(C- Caspase3)， B- cell lymphoma- 2(Bcl- 2) and Bcl- 2 associated X protein(Bax) were detected by Western blot. Results： Compared with those in the control group， the cell viability， GSH- PX content， SOD activity and Bcl- 2 protein expression level in the model group were significantly decreased(P＜0.05)，and the apoptosis ratio， MDA content as well as the protein expression levels of C-Caspase3 and Bax were significantly increased (P＜0.05)； in the low- concentration SGO group and the high- concentration SGO group， the apoptosis ratios，MDA contents as well as the protein expression levels of C- Caspase3 and Bax were significantly decreased(P＜0.05)， and the protein expression levels of cell viability， GSH- PX contents， SOD activity and Bcl- 2 were significantly increased when compared with those in the model group respectively(P＜ 0.05). Conclusion：SGO has a protective effect on H2O2-inducible oxidative damage of PC12 cells，whose mechanism is related to antioxidative stress damage and apoptosis.