Abstract: Correlation analysis showed that the correlation among total nitrogen, nicotine, protein, amino acid was extremely significant at 1 % level . Each smoking index and most of nitrogen compounds had close correlation. The multi regression equations between aroma, irritancy, taste, strength, sweetness and general quality existed at 10 % level of significance. It was pointed out that the medium N application level and low temperature yellowing or high moisture curing condition was good for the quality of tobacco leaf .