Abstract: By dilution method,10 strains were isolated from Zunyi tobacco rhizosphere soil and self- made bio organic fertilizer,which had antagonistic activity against the main pathogens of tobacco. Dual culture method was used to study the antagonistic effect of the strains on pathogens mentioned- above. The results showed that the growth inhibition rate of antagonistic bacteria Y2,Y3,Y4 and Y6 were very significant; the relative inhibitory rate of Y4 against Pseudomonas solanacearum was 400%. The antagonistic bacterium Y4 was primarily identified to be Cupriavidus necator through 16 S r DNA sequence analysis.