Antioxidant properties of selected vegetables from organic and conventional methods of cultivation in reducing oxidative stress were determined in the present study. Oxidative stress was induced in experimental rats by training them for 30 minutes on a treadmill moving at the speed of 20 m/min. Rats were fed four different diets containing separately lyophilized vegetables (cabbage, cooked potatoes, raw and cooked carrots) from organic and conventional systems of cultivation. At the end of the experimental period, plasma antioxidant capacity as well as lipid peroxide and protein content of the liver were determined. Antioxidant properties of selected vegetables were independent on the method of cultivation, but were the function of the type of vegetables, with cabbage characterized by the highest antioxidant activity. No significant effect on oxidative stress reduction was seen.