Abstract: In order to clarify the key contributors to the unfavorable odor of burley tobacco smoke, gel chromatography and gas chromatography-olfactometry-mass spectrometry ( GC-O-MS ) combined with sensory evaluation were used to separate and evaluate the particulate matter and total smoke trapping products of burley tobacco mainstream smoke. The results showed that the unfavorable characteristic odor of burley tobacco in the total smoke capture product was more obvious than that in the mainstream smoke particulate matter. A total of 46 volatile substances were identified from the total smoke capture of burley tobacco by GC-O-MS technology. Nine key characteristic components of burley tobacco smoke were identified by odor activity value calulation combined with sensory evaluation, namely trimethylamine, pyridine, 3-methylpyridine, 3-ethylpyridine, dimethyltrisulfide, p-cresol, indole, 3-methylindole and 2,3' -bipyridine. This study clarified the key components contributing to unfavorable odor in burley tobacco smoke, which could provide reference and guidance for the quality evaluation of burley tobacco raw materials and the cigarette formula.