The grape juice is a source and several studies co-related polyphenols with antiplaquetary and others biological effects of the grape juices. Resveratrol, a no-flavonoid compound, is one the polyphenols that has been attributed this actions (i.e.   antitummorogenesis). Nowadays there are a great variety of grape juices available for customers, among all of them there are the purple and white ones, and these can be produced by different grape cultivars. Today a great number of costumers look for   organic products which are produced without pesticides or others  chemicals and neither genetic modifications. In this study we investigated the possible antioxidant activity of two different grape juices, the organic and/or the conventional purple one. The antioxidant activity of the two grape juices was evaluated by an animal model, where 24 male Wistar rats (60 days-old and  200 + 25 g) were randomly divided into three groups: control that received vehicle (1 ml) and two  experimental groups organic or conventional juice twice a day (7 ul/ g weight in each way). After 30 days all the   animals were sacrificed and their blood were collected. We evaluated the lipid peroxidation level (TBARS assay), protein oxidative level (carbonyl assay) and   catalase (cat) and superoxide dismutase (sod) activities. The group treated with organic grape juice showed the highest SOD activity when compared with the conventional and control group(p<0.05). CAT activity showed higher in the organic group when compared with the conventional and control, and there is a positive correlation between the two enzymes (sod and cat) activities (r=0,707). We observed that after treatment curse time  animals that received the organic juice showed a greater antioxidant prtoection when compared to control or conventional juice, these results can be due to its richest  resveratrol content, there is a positive correlation among the resveratrol content and sod/cat activities (r= 0.721; 0.629 ; p<0.05), suggesting that this polyphenol can be one of responsible for this increased antioxidant defence.Carbonyl and lipid peroxidation levels were lower in the organic group when comparing to the other  groups, with statistic difference (p<0,05), proving that this juice could reduce   oxidative stress.  Taken into account our results  suggest that ingestion of purple grape juice, mainly the organic one,  induces a better  antioxidant  capacity when compared to conventional and this may be an important issue for further investigations in the area of biochemical functional  food.