In order to elucidate absorption, distribution and tolerance mechanisms of Brassica chinensis L. to chromium (Cr⁶⁺) stress, we grew two Brassica cultivars; ‘Meijiahua’(Cr⁶⁺stress tolerant) and ‘Sanyueman’(Cr⁶⁺stress sensitive) hydroponically in Hoagland 0, 10, 50 and 100 μmol·L^-1 Cr⁶⁺. The differencesin Cr absorbed contents and subcellular distribution, nonproteinthiol, phytochelatins(PCs) and antioxidant enzyme activities in shoots and roots were studied. The results were as follows: (1) the contents of Cr in shoots were significantly lower than those in the roots in both cultivars. The Cr root contents, Cr retention rate and the ratio of wallbounded Cr to total Cr in shoots and roots of ‘Meijiahua’ were significantly higher than those in ‘Sanyueman’, but the ratio of water soluble Cr to total Cr was opposite. (2) Cr⁶⁺ treatments at all concentrations significantly increased the concentrations of nonprotein thiol and phytochelatins (PCs) in shoots of both cultivars, but the increment in ‘Meijiahua’ was significantly higher than that in ‘Sanyueman’. (3) Under low concentration of Cr⁶⁺ (10 μmol·L^-1)，the activities of SOD, POD and CAT were significantly increased, but the extent of increase was significantly higher in ‘Meijiahua’ than that in ‘Sanyueman’. The activities of SOD, POD and CAT were significantly downregulated under high concentration of Cr⁶⁺ (100 μmol·L^-1), but the magnitude of downregulation in ‘Meijiahua’ was significantly lower than that in ‘Sanyueman’. These results indicated that under Cr⁶⁺ stress, as compared to ‘Sanyueman’, more Cr was distributed in cell walls in shoot and root in ‘Meijiahua’ to inhibit the transmembrane Cr to intracellular flow. Moreover, it has higher antioxidant enzyme activities and PCs content, so it showed a stronger tolerance to Cr⁶⁺.