Abstract: To explore the method for the control of Lonsdalea canker of poplar, based on the plate dilution method, 86 bacterial strains were isolated from rhizosphere soil of trees with Lonsdalea canker of poplar. Dual culture experiments results showed that 5 bacterial strains were of antibacterial activities against the pathogen Lonsdalea quercina. Control experiments with cutting indoor and trees in the field indicated that strains P2 and P4 were more effective than the other 3 strains, and control effectiveness in field can reach to 51.8% and 48.6% respectively. Strain P2 was identified as Bacillus subtilis, and the strain P4 was Streptomyces venezuelae. Four kinds of antibiotics and 2 kinds of fungicides were used to test inhibition effectiveness against the pathogen with dual culture experiments. Zhongshengmycin and Xinzhi had no obvious antibacterial effectiveness against the pathogen whereas polyoxin, streptomycin, ethylicin and amobam had. 100-fold dilution of agricultural streptomycin had better control effectiveness, prevention rate can reach to 38.2%. The experiments provided primary an approach for control of Lonsdalea canker of poplar.