Abstract: In order to study the variations of metabolites of alkaloids, sugars, organic acids, phenols in flue-cured tobacco during flue-curing process, a half leaf method and multivariate statistics analysis(PLS-DA and t-test)were used to screen the metabolites which changed significantly in the middle leaves of flue-cured tobacco(K326) before and after curing. The results showed that:1) The contents of inositol and high fatty acids(palmitic acid, linoleic acid, linolenic acid + oleic acid, stearic acid)decreased significantly after curing. 2) The contents of sugars (fructose, glucose), phenols (4-O-caffeoylquinic acid, scopoletin, p-coumaric acid, sinapic acid, ferulic acid)and anabasine increased significantly after curing.