Abstract: To identify the negative constituents contributing to offensive odors in sidestream smoke of burley and Maryland tobacco and their release characteristics, the sidestream smoke released from burley and Maryland tobacco made cigarettes were analyzed and the major sensorily negative components were determined by combination with olfactory analysis. A dual vacuum treatment was introduced to reduce the releases of the negative components in sidestream smoke during leaf threshing and redrying, and the reducing effects were evaluated. The results showed that: 1) Seventeen major negative components were identified in the sidestream smoke of burley and Maryland tobacco cigarettes, including acids, N-containing heterocycles, and phenolic compounds. 2) Dual vacuum treatment could effectively reduce the releases of the negative components in the sidestream of burley and Maryland tobacco cigarettes and improved the sensory perception of the sidestream smoke. The reducing effect was more obvious for burley tobacco than for Maryland tobacco. 3) The dual vacuum treatment showed relatively little effect on the mainstream smoke as a whole, only the sensory difference of β-damascenone was affected.