Antifungal effects of a soil-bacterium(TB-3) against several phytopathogenic fungi were studied. Conidial germinations of Fusarium oxysporum, Cochliobolus miyabeanus and several other phytopathogenic fungi were inhibited strongly in the broth of bacterium or n-butanol extracts of the broth, and if the condia germinated in the diluted solution, form of the germ-tube were abnormal. Spraying of the broth or n-butanol extracts of the broth had no effect on soil microflora, however, the spraying were effective to decrease the density of Fusarium oxysporum inoculated in the soil.