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建立了基质固相分散萃取-高效液相色谱串联质谱法(MSPD-HPLC-MS/MS)测定土壤中4种化工合成的苯脲类除草剂(异丙隆、绿麦隆、利谷隆、敌草隆)残留的分析方法.对基于球磨的基质固相分散萃取条件进行了详细优化,最终确定最佳条件为:0.5g土壤样品、1.5g弗罗里硅土作为分散剂与直径为8 mm的小钢珠—起球磨8 min后,转移至空的玻璃萃取小柱,用12 mL二氯甲烷-甲醇(8∶2,V∶V)洗脱,氮气吹干后用甲醇定容至0.6 mL,再经0.22 μm的滤膜抽滤后装入自动进样瓶中.用Syncronis C18反相色谱柱分离,以甲醇(A)～1‰甲酸溶液(B)为流动相进行梯度洗脱,选择反应监测(SRM)模式下进行检测.在最佳实验条件下,4种苯脲类除草剂在5～100 μg/kg范围内线性良好,相关系数R2在0.993 6～0.999 0.土壤样品的平均加标回收率在71.5％～102.4％,相对标准偏差为4.5％～9.2％.方法的检出限(S/N =3)在0.14～0.56 μg/kg.该方法简单、效率高、干扰少、回收率高,满足土壤中除草剂的残留分析要求.“,”An analytical method for simultaneous determination of four chemically synthesized urea herbicides (isoproturon,chlorotoluron,linuron and diiuron) is established by matrix solid-phase dispersion extraction (MSPD) with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).The dispersion extraction conditions are optimized based on the ball milled matrix solid-phase.The optimal conditions are as follows:0.5 g of Soil and 1.5 g of florisil are grinded with 8 mm of small steel balls for 8 minutes and then used as dispersants in the glass extraction column.12 mL of Mixed solvent consisting of 8∶2 volumetric ratio of chloromethane and methanol as eluent.The extract is concentrated to 0.6 mL with methanol,filtrated by 0.22μm of membrane and then moved to the automatic sample bottle.The measurement is performed under selective reaction monitoring mode (SRM) by using Syncronis C18 reverse phase column separation method and methanol (A)-1‰ formic acid solution (B) for the mobile phase gradient elution.Under the optimal condition,good linearity of four urea herbicides (chlorotoluron,isoproturon,diiuron and linuron) can be achieved when the concentrations of herbicides are in the range of 5 to 100 μg/kg.The correlation coefficients are ranged from 0.993 6 to 0.999 0.The average recoveries at two spiked levels are 71.5％-102.4％ with RSD less than 9.2％.The limits of detection for four urea herbicides are in the range of 0.14-0.56 μg.It is a simple and efficient method with less interference and high recovery rate,which can meet the analytical requirements of urea herbicides in soil.