Abstract: To fully investigate the quality of commercial tobacco extracts, 65 commercially available Yunnan tobacco extracts were sampled, and the volatile components of the extract samples were obtained by HS-SPME-GC/MS. The concept of aroma component relative index was first proposed and used to analyze the quality of the samples. Principal component analysis was used to establish the comprehensive evaluation model for 43 Yunnan tobacco extract samples, and the scoring model was verified by olfactory evaluation. The results showed that: 1) There were 28 common tobacco characteristic components in the 43 samples, including nicotine, neophytadiene, 4, 7, 9-megastigmatrien-3-one, geranylacetone, etc. 2) The relative indexes of myosmine, nicotyrine, anatabine and 2, 3'-bipyridine for most of the samples were less than 0.02, 0.05, 0.03 and 0.30, respectively, accounting for 97.67%, 95.35%, 100.00% and 97.67% of the total samples. 3) Principal component analysis was conducted for 17 tobacco characteristic components with correlation, and the principal component score expression was constructed. The cumulative contribution rate of the four principal components was more than 80%. There was a significant correlation between the principal component score and the olfactory evaluation indexes for these Yunnan tobacco extract samples, namely hay freshness, faint scent and sweet. The results of the scoring model from the representative samples were consistent with the results of the olfactory evaluation.