Abstract: In order to reveal the inhibitory effect of Bacllus atrophaeus SF1 on Fusarium oxysporum f.sp.lini,the effect of SF1 on the spore germination of pathogenic bacteria,the morphological changes of pathogens and the in vitro antibacterial rate of SF1 in different areas were studied.The results showed that Bacillus atrophaeus SF1 had inhibitory effect on the spores of Fusarium oxysporum fusarium graminearum,the spore germination rate was about 50%,the growth of SF1 hyphae had different inhibitory effect on different pathogens.The rate of bacteria was 56%.Bacillus atrophaeus SF1 has a significant inhibitory effect on the fungus of Fusarium oxysporum,which provide strain for the future development of flax fungus biocontrol agents.