Abstract: In order to search after appropriate nitrogen application dosage and proportion of phosphorus and potassium in the fertilizer composition, provide with a reasonable economic principle for scientific fertilization and guidance schemes for the production of quality sun-cured tobacco, an orthogonal design was used with small plot trials in the suitable growing areas to compare the effects on growth and development, yield, output value, and smoking quality of sun-cured tobacco, the results showed that the influences occurred in varying degrees while less or ruleless effects displaying on appearance quality and botanic characters respectively. At 75kg/hm2 of nitrogen application, the treatment had maximum yield and output value, whereas to 105kg/hm2, the output declined slightly, and nicotine content increased significantly at an average of more than 3.0 percent at this time. An increase of ratio of P to N heightened nicotine content but less influenced yield and output. More potassium added in fertilizer composition did not improve yield and output value, and the content of potassium in leaves of sun-cured tobacco has not markedly increased, whereas it conduced to reduce the content of nicotine. Therefore, the appropriate amount of nitrogen application for sun-cured tobacco should be controlled in 75kg/hm2 or below, and the suitable ratio of P to N advised to 0.5：1, only when lower level of phosphorus content in soil and pH＞7, the ratio could be increased to 1：1. The proper ratio of K to N is 2：1 and could be improved to 3：1 when lower level of potassium content in soil.