Abstract: The effect of slow-release fertilizer on the root system, photosynthetic characteristics and dry-matter accumulation in flue-cured tobacco was studied. The yield and output value of flue-cured tobacco leaf were also analyzed in the experiment. The results show that slow-release fertilizer increases tobacco root activity, chlorophyll content, net photosynthetic rate and dry-matter accumulation while reducing inter-cellular CO₂ concentration in flue-cured tobacco leaf. 45.45 g slow-release fertilizer for per plant has the most favorable impact on roots, leaf photosynthetic characteristics and dry-matter accumulation. Also 38.63 g slow-release fertilizer for per plant positively influences these variables. Yield and output value of the leaf are enhanced by slow-release fertilizer. Although yield of tobacco leaf decreases with decreasing application amount of slow-release fertilizer, tobacco output value increases due to the production of high quality tobacco leaf. 38.63 g slow-release fertilizer for per plant has the best effect on tobacco output.