Abstract: A bacterial community named Q6 with the ability of nicotine degrading was isolated from flue-cured tobacco leaves during aging. The results of PCR-DGGE analysis of 16S rDNA segment suggested that the bacterial community Q6 consisted of eight species. A bacterium named D1 was isolated from Q6 and identified as Agrobacterium tumefaciens by means of 16S rDNA sequence identification, morphological analysis, physiological and biochemical characterization. Comparing with bacterium D1, bacterial community Q6 presented better nicotine degrading activity at low temperature (20℃), pH=5 or pH ≥ 9, and high initial nicotine concentration (>1 g/L). The tests of tobacco leaf fermentation and resting cell inoculation showed that both Q6 and D1 were able to degrade nicotine in flue-cured tobacco leaves during aging. Nicotyrine, 2,3'-dipyridyl and cotinine, were detectable in the nicotine metabolites of both Q6 and D1. The results showed that the microorganisms on tobacco leaf surface might be able to degrade nicotine in tobacco leaves during aging, and further affect the aging process of tobacco. The isolated bacterial community or single strain could be used to degrade nicotine in tobacco leaves during aging to improve tobacco leaf quality, or to treat nicotine in tobacco wastes.