Abstract: In order to screen and evaluate the excellent biocontrol bacteria,four strains of biocontrol bacteria were selected in this experiment.The plate diffusion method was used to determine the plate bacteriostasis test of the dominant pathogen Fusarium oxysporum of soybean root rot and the preliminary study on the control effect of pot culture.The results showed that Bacillus subtilis HMGR-8 and Bacillus amyloliquefaciens NH2 showed good inhibitory effect on the target bacteria,the inhibition rates were 46.52%and 65.95%,respectively,and Trichoderma4-R-8 had strong inhibitory effect on target bacteria in a competitive way.The metabolites of Trichoderma MM2 inhibited the mycelial growth of target bacteria in addition to parasitism.In the pot experiment,the four biocontrol bacteria had different growth promoting effects.The disease indexes of the plants treated with Trichoderma MM2 suspension and Bacillus subtilis HMGR-8 fermentation broth separately and their mixture treatment were 25.33%,25.60%and 24.17%,respectively,which was not significantly different from that of carbendazim treatment of 17% and was significantly different from that of pathogen treatment of53.33%.The result suggests that antagonistic strains MM2 and HMGR-8 can reduce root rot severity significantly.