Abstract: In order to investigate the antibacterial properties of Bacillus amyloliquefaciens GM-1-1 sterile fermentation broth on Candida albicans and its antibacterial mechanism,the antibacterial effect against Candida albicans was detected by oxford cup method. Effects of fermentation broth on the spore germination,ultrastructure,biofilm determination ation and cell perrmeability of Candida albicans were determined by scanning electron microscopy,MTT method and spectrophotometry and the antibacterial mechanism was also discussed. The results showed that the GM-1-1 sterile fermentation broth had a significant inhibitory effect on Candida albicans,and the diameter of the inhibition zone was 39.5 mm. The inhibited Candida albicans continued to grow on the medium without the fermentation broth. The sterile fermentation broth had a strong inhibitory effect on the spore germination of Candida albicans. Scanning electron microscopy revealed a depression on the surface of the treated Candida albicans cells. The shape was irregular,and the cell wall was defective. The bacterial fermentation broth inhibited the formation of Candida albicans biofilm and increased the permeability of the cells. The paper preliminarily revealed the antibacterial mechanism of GM-1-1 sterile fermentation broth against Candida albicans,which laid a foundation for further research and application of the strain.