Abstract: To investigate the physiological response characteristics of ginger under Cd stress，the effects of the different Cd levels on active oxygen metabolism of ginger leaves with applying CdCl2 ? 2.5H2O solution were studied. The results showed that under Cd stress，with MDA content and electrolyte leakage rate increasing continuously， productivity rate and H2O2 content increased significantly in a dose and time dependent manner. At the seedling stage，the activities of superoxide dismutase（SOD），peroxidase（POD），catalase（CAT），glutathione reductase（GR），ascorbate acid（APX），monodehydroascorbate reductase（MDHAR），dehydroascorbate reductase（DHAR）and ascorbic acid oxidase（AAO）were enhanced markedly，and the contents of reduced ascorbic acid（AsA），total ascorbic acid（AsA + DHA），acid soluble SH，reduced glutathione（GSH）and phytochelatins were induced remarkably，and the ratios of AsA/DHA and GSH/GSSG also increased significantly. With the increase of Cd stress level and exposure duration，the activities of protective enzymes related and the content of antioxidants decreased significantly. The results suggested that ginger has the adaptability to Cd stress at short term（40 days）or lower Cd concentration stress. But under 120 days or higher Cd concentration stress，the antioxidant system in ginger leaves was damaged seriously and the balance of active oxygen metabolism was destroyed，and then the leaf membrane systems was damaged.

Key words: ginger, Cd stress, active oxygen metabolism