Abstract: For obtaining application potential antibacterial activity strains,Enterococcus faecalis 8-1 isolated from traditional fermented dairy kouminss in Inner Mongolia by the double agar diffusion method. After eliminating the effects of organic acid and catalase, the cell- free fermentation supernatant showed strong anti- Lister activity. After treatment with trypsin,pepsin,papain and proteinase K,its inhibitory activity destroyed,indicating that the antibacterial component was protein. This antibacterial substance showed stable antibacterial activity under acidic conditions andgood thermal stability. Organic solvents,metal ions and UV light did not affect the activity of the antibacterial substance,inhibitory activity enhanced with the combination of SDS and EDTA,and had a broad antibacterial spectrum against various species of Gram-positive bacteria and Gram-negative bacteria,which preliminary analysised the antimicrobial substance produced by 8-1 belong to bacteriocin-like substance.