Effects of various doses of 1,2,4-trichlorobenze on seed germination and seedling growth of soybean were studied. The results indicated that 50-200 micrograms.g-1 of 1,2,4-trichlorobenze had no effect on the percentage of seed germination, but delayed the rate of seedling growth. The seed germination was stopped by 300 micrograms.g-1 of 1,2,4-trichlorobenze. The most activity of SOD took place on the 4th day after sowing of soybean seed in the normal condition, then tended to be in a certain level with a little alteration. Under the various dose stress of 1,2,4-trichlorobenze, the activity of SOD in soybean hypocotyl was decreased, while MDA and protein contents as well as diameter of hypocotyls increased. Seedlings growth, fresh weight(FW), dry weight(DW) were inhibited, while the ratio of FW/DW didn't change. Damage-level of wheat seedlings was increased with increasing 1,2,4-trichlorobenze concentrations. Roots were more sensitive to 1,2,4-trichlorobenze-stress than hypocotyls.