Physalis peruviana (PP) is a widely used medicinal herb for treating cancer, malaria, asthma, hepatitis, dermatitis and rheumatism. In this study, the hot water extract (HWEPP) and extracts prepared from different concentrations of ethanol (20, 40, 60, 80 and 95% EtOH) from the whole plant were evaluated for antioxidant activities. Results displayed that at 100 μg/ml, the extract prepared from 95% EtOH exhibited the most potent inhibition rate (82.3%) on FeCl₂–ascorbic acid induced lipid peroxidation in rat liver homogenate. At concentrations 10—100 μg/ml, this extract also demonstrated the strongest superoxide anion scavenging and inhibitory effect on xanthine oxidase activities. In general, the ethanol extracts revealed a stronger antioxidant activity than α-tocopherol and HWEPP. Compared to α-tocopherol, the IC₅₀ value of 95% EtOH PP extract was lower in thiobarbituric acid test (IC₅₀=23.74 μg/ml vs. 26.71 μg/ml), in cytochrome c test (IC₅₀=10.40 μg/ml vs. 13.39 μg/ml) and in xanthine oxidase inhibition test (IC₅₀=8.97 μg/ml vs. 20.68 μg/ml). The present study concludes that ethanol extracts of PP possess good antioxidant activities, and the highest antioxidant properties were obtained from the 95% EtOH PP.