Abstract: Large amounts of bacteria have been found on aging flue-cured tobacco leaves. A bacterial community with the ability to decompose cellulose was isolated from aging flue-cured tobacco leaves. The effects of temperature, pH value and different cellulose source on the cellulase activity of bacterial community were further investigated. 16S rDNA PCR-DGGE technology was used to analyze bacterial community composition. The results showed that the bacterial community mainly consisted of five species. At 20 ℃, the cellulase activity of the bacterial community was very low. With the temperature increasing, the cellulase activity increased, and reached the peak at 60 ℃. When the temperature exceeded 60 ℃, the cellulase activity then decreased dramatically. With the pH value increasing from 3 to 8, the cellulase activity increased gradually, and reached the peak at pH 8. When the pH value increased from 8 to 9, the cellulose activity dropped sharply. The bacterial community was able to decompose the cellulose in the tobacco leaves, filter paper and the tobacco stalk. The cellulase activity of the bacterial community fermented in the tobacco leaves was significantly higher than that in the filter paper and tobacco stalk. In conclusion, the bacteria may have influence on the cellulose decomposition of tobacco leaves and affect the character of the tobacco during aging. The bacterial community may be used to decompose the cellulose of tobacco leaves and tobacco stalk in order to improve the quality of the tobacco leaves and stalk.