Abstract: By adopting the controlled atmosphere (CA) mellowing storage method of tobacco leaves, three different oxygen concentrations (≤ 2%, 2%-4%, 9%-11%) were set up to store 6 kinds of tobacco strips that reached the suitable period of use, and the effects of CA mellowing storage method at different oxygen concentrations on the appearance and sensory quality of tobacco strips were compared and analyzed. The results showed that the quality preservation effects of tobacco strips stored by the CA mellowing method with three different oxygen concentrations were better than that stored by the conventional natural mellowing method, which could effectively delay the decline rate of tobacco quality and prolong the storage and use time of tobacco strips. Among them, the tobacco strips stored by the CA mellowing method with less than 2% oxygen concentration had the best quality preservation effect, of which the quality level declined the most slowly and the quality maintained the longest. After 20 months of CA mellowing storage with less than 2% oxygen concentration, the appearance quality of tobacco strips such as Yunnang Malong B2F-2010, Yunnang Malong C3F-2010, Yunnang Malong X2F-2010, Argentina B1O-2010, Fujian Youxi C3F-2010 and Guizhou Wuchuan C3F-2010 decreased by 14.14%, 12.39%, 4.68%, 13.27%, 12.13% and 8.89%, respectively, and the sensory quality of them decreased by 8.02%, 5.17%, 12.54%, 5.16%, 6.38% and 8.38%, respectively.