The anoxia-reoxygenation model of cultured neonatal rats myocardial cells were developed, according to Laarse's method :anoxia and glucose deficiency for 60 min followed by reoxygenation and re-exposure to glucose for 30 min.The results showed that the intracellular malondialdehyde (MDA)content in the anoxia group was significantly increased,superoxides dismutase(SOD)activity was obviously reduced and membrane fluidity was decreased,all the changes were much more severe in the reoxygenation group.Total saponins of semen Ziziphi spinosae (ZS) could markedly and dose-dependently decrease MDA content，elevate SOD. activity and increase membrane fluidity. It proved the effects of ZS against lipid peroxidation induced by anoxia-reoxygenation.