An ultra performance liquid chromatographic(UPLC) method was developed for the determination of thiacloprid，flubendiamide and their metabolite residues in paddy soil and water.The paddy water was extracted with ethyl acetate,and the organic phase was concentrated to constant.The paddy soil was extracted with acetone-water and the extract was purified by liquid-liquid distribution.The optimization chromatographic conditions were as the follows：separation column：ACQUITY UPLC HSS T3 chromatographic column(2.1 mm×100 mm，1.8 μm)，mobile phase：acetonitrile-water，flow rate：0.3 mL?min-1，column temperature：35 ℃，sample volume：5 μL，detection wavelength：230 nm.Under the optimized conditions，the calibration curves of thiacloprid，flubendiamide and their metabolite residues showed good linearities in the range of 0.01-10.00 mg?L-1 with correlation coefficients of 1.000，1.000，0.999 9,respectively.The instrumental detection limits of three compounds were in the range of 0.001-0.002 mg?L-1，and their method detection limits were 0.000 4-0.001 0 mg?L-1 for water sample and 0.002 2-0.003 6 mg?kg-1 for soil sample.The spiked recoveries were in the range of 82%-106% with RSDs(n=5) of 0.81%-3.8%.With the advantages of easy operation，good separation effect，high sensitivity and accuracy，the proposed method was successfully applied in the determination of thiacloprid，flubendiamide and their metabolites in real samples.