Abstract: A split- plot experiment with two factors, nitrogen fertilizer application rate and remained leaf number, was conducted to study the effects of different treatments on photosynthetic characteristics of fluecured tobacco. The results showed that net photosynthetic rate of tobacco leaves was increased with the increment of nitrogen application rate and decreased with the increment of remained leaf number, the intercellular carbon dioxide concentration of tobacco leaves was decreased with the increment of nitrogen application rate and remained leaf number, the transpiration rate of tobacco leaves showed the increasedecrease trend with the increment of nitrogen application rate and remained leaf number, while the saturation vapor pressure deficit and stomatal conductance showed no clear change trend with the increment of nitrogen application rate and remained leaf number. Interaction between nitrogen application rate and remained leaf number existed, in order to increase the chlorophyll content at early growth stage, stomatal conductance, transpiration rate and net photosynthetic rate, A2B2 and A3B2 treatment showed better effect.