Abstract: To investigate the content variance of chemical components in flue-cured tobacco of different flavor styles,the contents of 25 chemical components of 88 C3F grade flue-cured tobacco samples of different cultivars from 18 provinces of China in 2008 and 2009 were determined,and the samples'smoking quality was evaluated.The determined data were descriptive statistics,variance analysis and principal component analysis.The results showed that:1) The contents of total alkaloids,chlorine,starch,petroleum ether extract and chlorogenic acid in full flavor style tobacco leaves and lutein, β-carotene and carotenoids in fresh flavor style tobacco leaves were significantly higher,while manganese,copper,zinc and rutin in full flavor style samples and iron,neochlorogenic acid and 4-hydroxyl-caffeoylquinicacid in medium flavor style samples were dramatically lower.The contents of total sugar and reducing sugar in medium and fresh flavor type samples were significantly higher than those in full flavor style samples.2) The first three principal components for the 3 flavor style tobaccos were composed mainly of nitrogen compounds,carbohydrates,polyphenols and plastid pigments.The principal components of full flavor style tobacco were in the order of polyphenols and plastid pigments,nitrogen compounds,carbohydrates,of medium flavor style tobacco were plastid pigments and nitrogen compounds, polyphenols, carbohydrates, and of fresh flavor style tobacco were composed of carbohydrates,nitrogen compounds,petroleum ether extract,manganese and chlorine, etc.