Abstract: 【Objective】The aim of the present study was to screen bacteria with nematicidal activity against the pine wood nematode(Bursaphelenchus xylophilus). 【Method】A total of 137 bacteria strains, which were isolated from the stems of pine trees in Nanjing, Luoyang and Shanghai, China, were assessed for nematicidal activity by immersion test with cultural filtrate and buffer suspension. 【Result】Cultural filtrates of three strains had stronger nematicidal activity than the other strains, and nematodes treated with these strains reached 100% mortality after 48 h and even exhibited decomposition when treated with the cultural filtrate of strain LYMC-3. The cultural filtrates of three strains, which were diluted 2, 4 and 10 times still showed high nematicidal activity. Nematicidal activity decreased with increasing dilution, and when nematodes were treated with 10× diluted filtrates for 48 h, the greatest observed mortality was 94.7% with strain LYMC-3. Moreover,the buffer suspension of strain NJSZ-13 had strong nematicidal activity against B. xylophilus, and 81.5% nematode mortality was achieved after 48 h treatment with 10⁵ cfu/mL buffer suspension of strain NJSZ-13. Based on morphology, physiological and biochemical characteristics, Biolog system identification, 16SrDNA sequences, and a phylogenetic tree, the strains LYMC-3 and NJSZ-13 were identified as Bacillus pumilus and B. cereus, respectively.【Conclusion】Two strains of bacteria LYMC-3 and NJSZ-13 with high nematicidal activity which were isolated from the stems of pine trees could provide potential solution for biological control of Bursaphelenchus xylophilus.