建立了水稻中提取苄嘧磺隆和苯噻酰草胺残留量的液相色谱-质谱/质谱测定方法UPLC-MS /MS。稻米样品经乙腈匀浆，上清液经氮气吹干浓缩，过PSA固相萃取柱净化，经UPLC-MS/MS测定，外标法定量。苄嘧磺隆在稻米中的最低检出量为0.1 ng，最低检出浓度为0.02 mg/kg，添加回收率为77.7%～91.5%，稻米的RSD为2.9%～8.5%；苯噻酰草胺在稻米中的最低检出量为0.05 ng，最低检出浓度为0.01 mg/kg，添加回收率为94.0%～109.0%，稻米的RSD为5.0%～8.2%。建立方法准确、快速、灵敏度高，能够满足苄嘧磺隆和苯噻酰草胺残留量分析的要求。

Established the detection of bensulfuron-methyl and mefenacet residues in rice by UPLC-MS/MS methods. Rice samples were homogenized in acetonitrile, the supernatant was dried by nitrogen concentration, over PSA solid phase extraction（SPE）, measured by UPLC-MS/MS, external standard. Bensulfuron-methyl minimum detectable amount of rice is 0.1ng, the minimum detectable concentration of 0.02 mg/kg, recoveries were 77.7%~91.5%, rice RSD 2.9% to 8.5%; mefenacet in rice in the minimum detectable amount of 0.05 ng, the minimum detectable concentration of 0.01 mg/kg, recoveries were 94.0%~109.0%, rice RSD 5.0% to 8.2%. The method is accurate, rapid, sensitive and able to meet bensulfuron-methyl and mefenacet residue analysis.