摘要：By means of the X\|ray diffraction method, quantum pharmacology analysis and quantitative structure\|activity relationships (QSAR) analysis, the structure\|activity relationships of the herbicidal sulfonylureas and fused heterocyclic sulfonamides were systematically studied. The results showed that the structure\|activity relationships of these two kinds of herbicides were identical and that the heterocyclic ring and sulfonyl moiety in the molecules were their pharmacophores which likely bind in the same receptor sites of acetolactate synthase (ALS). According to these results, the initial model of these two kinds of herbicides binding with the receptor was put forward.