Abstract: The growth pattern, chlorophyll content, lipid peroxidation as well as the activities of superoxide dismutase (SOD), Glutathione Peroxidases (GP) and catalase (CAT) were studied in the radicles, roots and shoots of Vigna unguiculata (the common beans) and Zea mays (maize) grown in soils contaminated with two nickel concentrations {0.1% (65 μM) and 0.2% (130 μM)}. Two hundred and seventy of either bean or maize seeds were germinated in these contaminated soils and 10 of each germinated plants were harvested after either the 7th, 14th and 21st days. The study observed chlorosis and stunted growth in the nickel-treated plants. Nickel accumulated in the tissues in increasing order of the radicle, root and the shoot. Treatment of the plants with 0.1% or 0.2% nickel did significantly (p<0.05) affected the activities of SOD, CAT and GP in the tissues studied throughout the experimental periods. Lipid peroxidation as measured by the production of malondialdehyde was significantly increased (p<0.05) in the plants grown on nickel-contaminated soils compared with the controls. These results indicate that nickel cause oxidative damage in Vigna unguiculata and Zea mays and as an adaptive feature, they increase the activities of antioxidant enzymes of the radicle, root and shoot.