Objective: To study the effects of Tengcha flavonoids (TCF) on scavenging oxygen free radicals and inhibiting lipid-peroxidation., Methods: The effects of TCF on scavenging superoxide anion radical induced by xanthine-xanthine oxidase, inhibiting lipid-peroxidation of heart, liver, brain tissue homogenate and mitochondria induced by Fe2+ -VitC, Fe2+ -H2O2, Fe-Cys were discussed by TBA spectrometric method., Results: TCF could significantly inhibit the superoxide anion radical, IC50 is 14.7 mg/L, and the lipid peroxidation of liver homogenate and mitochondria induced by auto-oxidation and induced-oxidation. The inhibition exhibited concentration-dependent manner., Conclusion: It indicated that TCF could scavenge oxygen free radicals and was capable of prophylacticly antagonizing against the oxidative injury by superoxide anion.