Abstract: A GC-MS/MS method was established for simultaneous determination of 27 pesticides in fresh tobacco leaves. Using acetonitrile as extraction solvent and including a cleanup step with primary secondary amine（PSA） ， graphitized carbon black（GCB）and C 18 to reduce the high matrix effect found in these products. The samples were quantified using external standard with the matrix matched standard calibration curve method. Good linearities of two suckercides were observed in the range of 10-1 000 µg/kg with correlation coefficients more than 0.995. The limits of detection（LOD）and the limits of quantification（LOQ）for 27 pesticides were 0.4-2.9 μg/kg and 1.4-9.6 μg/kg， respectively. The average recoveries at three spiked concentration levels ranged from 71.8% to 108.1%. The repeatabilities expressed as relative standard deviations（RSD）ranged from 3.2% to 11.8%. The method was suitable for the determination of 27 pesticide residues in fresh tobacco leaves.