The tobacco flavours include four type for virginia, burley, cigar and reaction. The virginia type can blend the tobacco odor with green, winy and sweet odor but not too strong. The odor of burley type is very strong and can decrease the irritation of tobacco . The cigar type can modify and blend the cigar odor to maintain original characteristic odor and decrease the irritation of cigar. The reaction type is odorless, When smoke the cigarettes, the reaction flavors can be decomposed and gone out like the odor of tobacco, so it can modify the smell, cover the by-odor, enhance tobacco odor as well as soften the tobacco leaf.