The oxidative damage model of PC12 cells induced by H₂O₂ was established to study the protective effect of neutral polysaccharide from Brassica rapa L.(BRNP) on oxidative damage of PC12 cells and its primary mechanism. Cell survival rate was detected by CCK-8 method.Lactate dehydrogenase (LDH) was used to detect the protective effect of H₂O₂ on oxidative damage of PC12 cells.The effect of BRNP on mitochondrial membrane potential induced by H₂O₂ in PC12 cells was detected by JC-1 method.The expression levels of Bax,Bcl-2 and Caspase-3 in H₂O₂-induced PC12 cells were detected by Western blot.The results showed that BRNP had no obvious cytotoxicity to PC12 cells.The molding concentration and time of H₂O₂ were 300 μmol/L and 4 h,respectively.BRNP can alleviate the oxidative damage of PC12 cells induced by H₂O₂ to a certain extent.BRNP can reduce the damage of H₂O₂ on mitochondrial membrane potential of PC12 cells.The expression levels of Bax and Caspase-3 protein were significantly decreased after different doses of BRNP intervention in PC12 cells (P<0.05).The expression level of Bcl-2 protein was significantly increased (P<0.05).In conclusion,BRNP can improve the H₂O₂-induced oxidative stress damage of PC12 cells and protect their cell function,and its mechanism may be related to inhibiting the production of LDH in cells,increasing the activity of antioxidant enzymes and the expression level of apoptotic proteins.