Objective To investigate the effect of betulin on Aβ_25-35 -induced oxidative stress and apoptosis of PC12 cells. Methods PC12 cells were treated with 40 μmol / L of Aβ_25-35 . The cells were randomly divided into control group, Aβ_25-35 group, NAC group, and betulin 5, 10 and 20 μmol / L groups. Apoptosis was detected by V-FITC/ PI double staining flow cytometry; mitochondrial membrane potential was detected by JC-1 kit; LDH, MDA and SOD levels were detected by LDH, MDA and SOD kits, respectively; the enzyme activity of caspase-3, caspase-8, caspase-9 and Cyt c was detected by colorimetry; the activity and expression of Bcl 2, Bax, caspase-3, caspase-8, caspase-9 and Cyt C were detected by western blotting. Results Compared with the Aβ_25-35 group, betulin and NAC improved the cell survival rate and SOD activity ( P < 0. 01), reduced the LDH release rate and apoptosis rate ( P < 0. 01), inhibited caspase - 3, caspase-8, caspase-9 and Cyt c enzyme activity (P < 0. 01), and downregulated Bax, caspase-3, caspase-8, caspase- 9 and Cyt c enzyme activity (P < 0. 01) and expression level (P < 0. 01). In contrast, these treatments upregulated the activity and expression of Bcl2 ( P< 0. 01 ). Conclusions Betulin inhibited the Aβ_25-35 -induced apoptosis. The mechanism may be related to the reduction in ROS production, thus reducing the level of oxidative stress, and thereby inhibiting apoptosis.