Abstract: Abstract: Maturity is the central element of tobacco quality, so appropriate harvest maturity is very important to tobacco quality of Hongda. After analysis and evaluation of raw tobacco with different harvest maturity, the results showed that no significant difference was in visual quality, balanced carbon and nitrogen metabolism and harmonious chemical composition were in 6-7 tenth yellow for lower tobacco leaves, 8-9 tenth yellow for middle tobacco leaves, and 9-10 tenth yellow for upper tobacco leaves, and similar results were in smoking quality.