Abstract: To investigate the variation patterns in pyrolysis characteristics of cigar tobacco leaves during fermentation, a multi-dimensional characterization was conducted on cigar tobacco leaves at different fermentation stages using techniques including proximate analysis, ultimate analysis, and TG-FTIR. The analysis focused on the material and elemental composition, thermogravimetric behavior under nitrogen atmosphere, and evolved gas components. The pyrolysis activation energy at different fermentation stages was calculated using both the Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods to explore differences in pyrolysis characteristics. The results indicated that: 1)During fermentation, the content of volatile matter, carbon, nitrogen, and the C/O ratio decreased, while the ash content increased relatively, leading to a higher residual mass fraction after pyrolysis. 2)As fermentation progressed, the peak temperatures within the pyrolysis temperature range of 100-400 ℃ shifted toward lower temperature zones, and the maximum weight loss peak appeared earlier. Moreover, within this temperature range, the peak release temperatures of characteristic substances in the evolved gases decreased with fermentation. 3)Kinetic analysis revealed that the pyrolysis activation energy of the cigar tobacco leaves gradually increased with the progression of the pyrolysis reaction (conversion α=0.1-0.8), while the average pyrolysis activation energy decreased with prolonged fermentation time.