Replica platings among 9 species bacteria isolating from the stems, branches and leaves of poplar infected by INA bacterial canker were made.They are the pathogen Pantoea agglomerans , 7 species of Bacillus , and Pseudomonas syringa . Results showed that the majority of poplar inhabiting bacteria are interspecific symbiont, the minority have antagonistic action in interspecies. It provided basic studies for further explore the roles of the poplar inhabiting bacteria in natural contracting of poplar bacterial canker, and also further select antagonistic microbe for effective biocontrol to poplar bacterial canker.