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A multi-residue analysis method was developed for the determination of 38 kinds of pesticides in nuts (almonds, peanuts, cashew nuts and walnuts) by QuEChERS-ultra-high performance liquid chromatography-tandem mass spectrometry. The pesticide residues were extracted with acetonitrile. The extract was cleaned up with PSA, C-18 and Oasis PRiME HLB, and then analyzed by UPLC-MS/MS with multiple reaction monitoring (MRM) mode. External standard method was employed to quantify. The limits of detection (LODs, S/N = 3) of this method were between 0.01 and 10 mu g/kg, and the limits of quantitation (LOQs, S/N = 10) were between 0.05-20 mu g/kg. All of the tested pesticides showed good linear relationship (r>0. 991). The practical samples were determined at three spiked levels and the average recoveries were between 51.0% and 126.0%. The RSDs were less than 20%. This method was simple, sensitive and accurate, and could be used for the routine analysis of pesticide residues in nuts.