Abstract: The effects of selenium (Se) application methods on the quality of middle leaves of flue-cured tobacco were studied by field experiment, including soil application of Se(30, 40, 50 g/666.7m2), foliar application of Se (500, 1 000 μg/plant) and non-selenium. The results showed that, with the increase of Se rate, the reducing sugar and total sugar contents declined, the protein, nicotine, total nitrogen and K content increased, and the chlorine content had no changed. Suitable Se had no significant negative impact on sensory evaluation of middle leaves. Suitable Se reduced harmful composition of smoke effectively, such as total particulate matter, tar and so on, to improve safety of tobacco leaves.