Abstract: Eighteen nicotine-degrading bacteria were isolated from fresh and healthy tobacco leaves collected from 5 counties (Tengchong,Wenshan,MiLe,Shilin and Yuxi) in Yunnan Province,and two strains which showed higher nicotine-degrading abilities were identified as Pseudomonas cedrina subsp.cedrina based on their 16S rDNA sequences,morphological and biochemical characteristics.The two strains could utilize nicotine as the sole source of carbon and nitrogen,degrading nicotine (＜3.0g/L) within 18h at 28℃ and pH=7.0.The nicotine-degrading cycle was shorter than other previously reported bacteria with the same abilities.Therefore,the two stains have potential industrial prospects in nicotine-degrading.It is the first time of Pseudomonas cedrina subsp.cedrina being reported for degrading nicotine.