Abstract: To provide theoretical basis for the study of Ulmus pumila resistance to single and compound soil pollution and ecological restoration of compound contaminated areas. the effects of different concentrations of Cd stress and salt stress on chlorophyll, malondialdehyde（MDA）, peroxidase（POD） and superoxide dismutase（SOD） of Ulmus pumila seedlings were studied by soil culture experiment. The results showed that the effects of Cd and NaCl combined stress on chlorophyll, MDA, POD and SOD of Ulmus pumila were more obvious than that of Cd and NaCl single stress. In the process of stress, chlorophyll content of Ulmus pumila increased with the increase of single and compound stress gradient. The MDA content of Ulmus pumila decreased with the increase of single and compound stress gradients. POD activity and SOD activity increased with low concentration and decreased with high concentration under single and combined stress. The results showed that POD and SOD activities of Ulmus pumila were inhibited in different degrees when Cd stress level was higher than 200 mg/L and NaCl stress level was higher than 500 mmol/L, and the damage effect of composite stress on Ulmus pumila was more obvious than that of single stress.