Abstract: The influences of 4 plant growth-promoting rhizobacteria(PGPR)on tomato seedling growth and root-knot nematode,Meloidogyne incognita were investigated under greenhouse conditions.Results showed that the inoculation with Bacillus polymyxa or Bacillus sp.B697 could significantly increase plant height and dry mass,while B.megaterium and Azospirillum sp.showed fewer effects on seedling growth.The treatment with B.polymyxa+M.incognita or Bacillus sp.B697+M.incognita could significantly decrease the number of the second stage juvenile,the female,egg-mass per gram roots,eggs per egg-mass,the disease incidence and disease indexes,compared to the treatment with M.incognita. The control effect of B.polymyxa,Bacillus sp.B697,B.megaterium and Azospirillum sp.was 65.4%,68.2%,53.8%,and 53.8%respectively.It was suggested that there should be some biocontrol potential for B.polymyxa and Bacillus sp.A135 under field conditions.