Abstract: The carbendazol residues in 35 tobacco samples were determined by LC/MS.Tobacco samples were extracted with methanol-HCl aqueous solution,then cleaned up with solid-phase extraction,and detected by reversed-phase LC/MS with XTerra MSC₁₈ column,using acetonitrile and 20 mmol/L ammonium acetate aqueous solution as a mobile phase at the flow rate of 0.2 mL/minute.The results showed that the limit of detection and average recoveries of carbendazol were 1.0 μg/kg and 90.8% to 102.2%,respectively,with the relative standard deviations(RSD) of 2.05% to 4.21%.The detection rate of carbendazol residues was about one fourth among the samples with the concentrations of 5.7 to 112 μg/kg.