Tobacco structure after shredding, baking, flavoring and storage was analyzed by the gray correlation method to determine the optimal shredding size, and then the tobacco structure was optimized by using a tobacco cutting device. The results showed that the short cigarette had the problems of low full strands rate and high long strands rate. It was found that the full strands rate was less than 80.00%, and the long strands rate was more than 40.00%; the middle strands rate ranged from 20.00% to 30.00%, and the broken strands rate was less than 2.00%. There was strong positive relation between the size of 6.50~8.00 mm after shredding and that of 3.35~8.00 mm after baking, the size of 3.35~10.00 mm after baking and that of 2.50~6.50 mm after flavoring, the size of 3.35~8.00 mm after flavoring, and the size of 3.35~8.00 mm after storage. After cutting 6.50~8.00 mm tobacco with the tobacco cutting device, the long strands rate was reduced by 10.79%, but the middle strands rate increased by 15.13%. The cigarette weight standard deviation, pressure drop standard deviation, the hardness standard deviation and the loss of tobacco from cigarette end decreased by 9.52%, 2.11%, 22.46%, and 23.21%, respectively. And then the quality of cigarette was significantly improved.