Abstract: This study was conducted for chemical components of four sections ( leaf tip, leaf center, leaf base and leaf margin) flue - cured tobacco samples with representative grades ( B2F, C3F, X2F) of 3 stalk positions from 9 ecological tobacco- growing areas. The results showed that the chemical components of flue cured tobacco samples with representative grades ( B2F, C3F, X2F) of 3 stalk positions had significant differences among 9 ecological tobacco- growing areas; The chemical components of flue- cured tobacco samples with representative grades( B2F, C3F, X2F) of 3 stalk positions were classified 5 groups based on the euclidean distance, because the distance was shorter between the samples of same group, the comparability was higher; so chemical components of flue- cured tobacco samples of different sections had fairly similarity in the same groups, at the same time the main chemical components had significant differences among 5 groups.