Abstract: [ Objective ]To identify and biologically characterize the Enterococcus faecium stain M74, and to lay a foundation for its utilization in feed additive production. [ Methods ]The strain was identified to species level by 16S rDNA PC R and sequencing; the tolerance of the strain to acid, bile salt, high temperature, and antibiotics were assessed by single factor test; the feature of organic acids production of the strain was investigated; the interactions between the stain and probiotics were evaluated; the antibacterial ability of the stain against the pathogenic bacteria was determined. [ Results ] The stain was molecularly identified as Enterococcus faecium; after the treatment with pH value of 3 and bile salt concentration of 0.3% for 3 hours, the survival rate of the M74 stain was 11.57% and 0.64%, respectively; after the treatment at a 60 ℃ temperature condition for 10 minutes, the survival rate of the M74 stain was 25.42%; M74 stain expressed different levels of resistance against various antibiotics; the highest organic acids production was observed in acetic acid whose yield reached up to 4 620.15 μg/mL; M74 stain had growth inhibitory effect on the other probiotics when it was firstly cultured in the plate; M74 stain also exhibited good antibacterial ability against Escherichia coli and Salmonellae. [Conclusion] Enterococcusfaecium stain M74 is demonstrated to possess good growth resistance and growth inhibitory effect on pathogenic bacteria, indicating its application value in feed additive production.