as an important ecological factor, the illumination plays an important role in the quality of the flue cured tobacco seeding; in the experiment, LED light source is used to conduct the short- distance irradiation and conducted the irradiation on the tobacco seeding point by point with different wavelengths at different positions and spaces, for the flue-cured tobacco seedling with intensive cultivation at low position, it is needed to fill the light, and to adjust the light environment for the growth of flue-cured tobacco seedlings in the process of greenhouse seedling. The research on the photosynthetic productivity, photosynthetic characteristics of tobacco seedlings and the measures to fill light in different light environments has an impact on the quality of the flue-cured tobacco floating seedling sprout and the growth of tobacco seedling.