Abstract: To investigate the effects of ecological factors on the metabolic characteristics of fresh tobacco leaves, according to flavor type regionalization of flue-cured tobacco in China, the correlations between characteristic metabolites (lipids, nitrogen compounds, carbohydrates, organic acid compounds, nucleic acid compounds, sterols) of fresh tobacco leaves and different meteorological factors were analyzed and the ecological causes of those metabolites were studied based on the eight typical flavor types and the meteorological data. The results showed that, the characteristic metabolites had certain correlations with ecological conditions in each flavor type region. The variations of the ecological parameters, such as temperature, sunshine hours and precipitation could explain the accumulations of some characteristic metabolites, which indicated that the metabolic characteristics of fresh tobacco leaves closely correlated to the environment and ecology. Among them, the climatic factors that had close correlations with characteristic metabolites were temperature and sunshine hours during middle to late growing stage.