Abstract: A hydroponic experiment was carried out to study the effects of different Cd levels on the growth and the activities of antioxidant enzymes in two cultivars of Brassica campestris L．ssp．chinensis(L．) Makino．Cd 1 mg·L^-1 didn’t significantly afect the growth and chlorophyll content of both cultivars (except the shoot dry mass of‘ 'Hangzhou Youdonger’)，Cd 10 mg·L^-1 significantly inhibited the growth and leaf chlorophyll content of both cuhivars(except the root dry mass of‘ 'Huqing 1’)．，nle generation of 0₂^-. and H₂O₂，content increased under Cd exposure，and mal0ndialdehyde(MDA)accumulated．The activities of catalase (CAT) and peroxidase (POD) of‘ Huqing 1’ and ascorbate peroxidase (APX) of ‘Hangzhou Youdonger’were significantly increased at Cd 1 mg·L^-1．Cd 10 mg·L^-1 significantly decreased the activities of superoxide dismutase (SOD)，CAT and APX，and significantly enhanced t}Ie activities of dehydroascorbate reductase (DR) and glutathione reductase (GR) in both cuhivars．

Key words: Brassica campestris L． ssp．chinensis (L．) Makino, Cadmium, Active oxygen, Growth, Antioxidant enzyme