Abstract: Climate factors at tobacco-growing areas in Hunan Province and the influence of heat and precipitation on chemical components of flue-cured tobacco leaves were analyzed.The results indicated that Hunan tobacco growing areas had suitable temperature,a long periods of time with daily average temperature of ≥20℃,more than 2600℃ for accumulated temperature of ≥10℃ and small temperature difference between day and night.But precipitation and air humidity were high and sunlight percentage was low during growing periods.With total precipitation during vigorous growing stage and day-and-night temperature difference decreasing,and with average temperature during root extending and vigorous growing stages and accumulated temperature of ≥10℃ increasing, it could be helpful for the development of high quality flue-cured tobacco leaves.Hunan tobacco-growing areas could be classified into three groups by cluster analysis method.The first group mainly included areas of South,Middle and East Hunan;The second group mainly included areas of West Hunan;The third group mainly included areas of Northwest Hunan.The climate factors and the tobacco quality traits for different groups were briefly described.

Key words: Hunan tobacco-growing areas, Hunan tobacco-growing areas, Flue-cured tobacco leaf, Climate factors, Chemical components