The antioxidant activitiesof methanol extracts of twenty one vegetables were tested using the method of 1,1-diphenyl-2-picryl hydrazyl (DPPH) reactivity and TBARS substance assay in vitro. The methanol extracts of the leaves from three plants such as Aster scaber, Chrysanthemum coronarium, Petasites japonicus were found to be th most effective on DPPH radical scavenging activity. The next effective ones were the leaves of Capsicum annuum, the peels of Ipomoea batatas and Solanum tuberosum, the stems and leaves of Ipomoea batatas, the levels of Solanum melongena, the fruits of Solanum melongena, the green fruits (seed) of Capsicum ammuum in order, and the others did not show a considerable activity. When tested on lipid peroxidation using a lipid peroxidation generation system mediated by $H_{2}O_{2}/Fe^{2+}$ in rat liver homogenates. the peels of Cucumis melo, the leaves and the fruits of Solanum melongena, of Solanum melongena, The levels of Aster scaber and Chrysanthemum coronarium, the stems and leaves of Ipomoea batatas and the peels of Ipomoea batatas were found to exhibit a good protective activity against lipid peroxidatian in the order of effectiveness.