Abstract: We investigated the effect of exogenous nitrogen on the growth of white clover (Trifolium repens) under cadmium stress and on Cd toxicity. White clover plants grown in pots were treated with N and/or Cd, and their growth, biomass, chlorophyll content, antioxidant enzyme activity, Cd content, glutathione (GSH) content, and phytochelatins content were determined. Treatment with Cd significantly inhibited the growth and decreased the chlorophyll content of white clover. However, applications of both Cd and N to the soil promoted white clover biomass and chlorophyll content, as compared with the control. The addition of N under Cd stress enhanced plant growth and chlorophyll content, and increased the activities of peroxidase, superoxide dismutase, and catalase, as well as increasing the Cd content. Treatment with Cd alone increased the phytochelatins content and significantly reduced the GSH content. Treatment with N increased the GSH and phytochelatins contents under Cd stress. These results indicated that exogenous N can effectively alleviate Cd toxicity to white clover.