Abstract: The biological activity of the herbicide antidote 3- dichloracetyl - 2,5- dimethyl - 2- ethyl - 1,3- oxazolidine was researched to reduce injury of herbicide Chlorsulfuron to stubble sensitivity crops of the maize,etc. The physiological indexes of maize main plant height, fresh weight, yield, branch amino acid content in maize seedling, etc were measured with the bioassay methods in laboratory potted plant and plot test. The result indicated that the plot has used by chlorsulfuron last year, When maize will be seeded next year, the injure may be reduced by soaking seed, blending seed, mixed spraying and spraying leaf, etc. with 3- dichloracetyl - 2,5- dimethyl - 2- ethyl - 1,3- oxazolidine. The effect of mixed spraying is best among them, its yield increased 99.41% than that of CK, and the method of soaking seed is next to mixed spraying, for 95.65% of the comparison. The corn may be planted after using chlorsulfuron in soil when the residual quantity of chlorsulfuron less than 5μg/kg by using herbicide antidote.