Residue of imidacloprid and buprofezin in rice straw, soil, water and rice were extracted by acetonitrile and cleanup with florisil and NH2 SPE mini column, and determined by reversed phase column HPLC equipped with DAD and GC equipped with µECD. The results showed that the fortified recoveries of imidacloprid and buprofezin in samples were 89.2%-106.4%. The coefficients of variation were 1.7%-13.2%. The minimal detectable quantity of imidacloprid was 5×10-10 g, the minimal detectable quantity of buprofezin was 2×10-11 g. The results showed that the half-life of degradation for imidacloprid were 1.7-2.2, 2.3-2.8 and 1.3-2.0 d in straw, soil and water,respectively. The half-life of degradation for buprofezin were 2.3-2.9, 9.4-12.7 and 1.8-2.3 d in straw, soil and water, respectively. The terminal residues of imidacloprid were less than 0.05 mg·kg-1 and the terminal residues of buprofezin were less than 0.3 mg·kg-1 in rice with the application dosage, sprayed 2 times and last spray was 14 d before harvest. The terminal residues of two pesticides were all less than the maximum residue limits provided China.% 采用乙腈提取水稻植株、土壤、田水、稻米中的吡虫啉和噻嗪酮，经氟罗里硅土固相萃取小柱和氨基固相萃取小柱净化，分别采用反相HPLC-DAD和GC-μECD检测。结果表明，样本中吡虫啉和噻嗪酮添加回收率均在89.2%~106.4%，变异系数为1.7%~13.2%，吡虫啉最小检出量为5×10-10 g，噻嗪酮最小检出量为2×10-11 g。吡虫啉在植株、土壤和田水的半衰期分别为1.7~2.2、2.3~2.8和1.3~2.0 d；噻嗪酮在植株、土壤和田水的半衰期分别为2.3~2.9、9.4~12.7和1.8~2.3 d。16%吡虫啉·噻嗪酮可湿性粉剂按照推荐施用剂量，最多施药两次，最后一次施药距采收间隔期为14 d，收获稻米中吡虫啉的最终残留量均低于0.05 mg·kg-1，噻嗪酮的最终残留量均低于0.3 mg·kg-1。两种农药的最终残留量均未超过我国规定的最大残留限量值。
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