A heart-cutting two dimensional liquid chromatography coupled with tandem mass spectrometry method was developed for the analysis of tobacco-specific nitrosamines at low concentration level in Virginia type cigarette smoke.A strong cation exchange column was utilized for the first dimensional separation,which effectively removed acidic and neutral components in the smoke,followed by a reversed phase liquid chromatography coupled with tandem mass spectrometric analysis.To capture components of the tobacco-specific nitrosamines in the effluent on the trapping column,a compensating pump was applied for on-line dilution and pH adjustment during the period of the tobacco-specific nitrosamines fraction transferring and enrichment.High sensitive determination of the tobacco-specific nitrosamines in mainstream cigarette smoke was achieved by isotope deuterated internal standards under the multiple reaction monitoring mode.Compared with traditional methodologies,the method was almost no matrix interference.Limits of quantity for the tobacco-specific nitrosamines were within 0.027 - 0.094 ng/mL.And the results showed good reproducibility and accuracy.Finally,the new method was applied to analysis of the Kentucky reference cigarettes and the results agreed well with joint experiments of Cooperation Centre for Scientific Research Relative to Tobacco.