An ultra performance liquid chromatography-tandem mass spectrometric（UPLC-MS/MS） method was developed for the rapid determination of six alkaloids in tobacco.The sample pretreatment and parameter separation conditions were optimized.The samples were extracted with deionized water,and separated on UPLC BEH C18 chromatographic column.The mass spectrometer with electrospray in positive ionization was operated under multiple reaction monitoring（MRM）mode.Six alkaloids was quantified by the isotope internal standard method to avoid matrix effects.The result indicated that,the calibration curves of six alkaloids were in the range of 0.1-8 000 μg/L.The spiked recoveries ranged from 87% to 115% with relative standard deviations of 1.9%-9.7%.The limits of detection ranged from 50 μg/kg to 1 250 μg/kg.This method was simple,accurate and reproducible,and could be used for the rapid analysis of six alkaloids in batches of tobacco samples.