Abstract: The commercial large volume headspace sampling system was improved. The cold trap was wrapped with insulation cotton to keep at 220 ℃ as a high temperature module, and the diversion port was moved to the high temperature module. The multidimensional trap was pre-heated to 210 ℃ under sealed condition to allow the headspace components to desorb and inject the sample instantly. The top of the cigarette packaging in a small box was opened, and quickly placed into a large volume headspace sample bottle. 1 mL of methanol solution containing 0.4 mg·L⁻¹ deuterated styrene (internal standard) was added, and the bottle was sealed. The mixture was heated and equilibrated at 40 ℃ for 40 min, and separated on a DB-HeavyWAX chromatographic column according to the column heating program. Electron impact ion (EI) source and full scan (SCAN) mode were adopted in mass spectrometry analysis. As shown by the results, the RSDs (n=6) of the determined values of most compounds were less than 6.0%. This method was used for analysis of different types of cigarette samples, and there were significant differences in unpacking breath compounds of different types of cigarettes, with the main differential compounds of pyrazines, terpenes, esters, and acids.