The 28 strains of lactic acid bacteria was isolated from Mongolian dried beef. The antibacterial activity of 28 strains of lactic acid bacteria were detected by Escherichia coli， Staphylococcus aureus and Listeria monocytogenes as indicator bacteria. The strain 37X-3 and strain 37X-13 have strong bacteriostatic ability of the three kinds of indicator bacteria， and all the bacteriostatic activities are lost after pepsin and proteinase K treatment， indicating that the two lactic acid bacteria exert bacteriostasis by producing bacteriocins effect. The 37X-3 produced Pediococcus pentosaceus， 37X-13 produced Pediocin acidilactici by the identification of phenotype， physiological， biochemical and genetic type. The 2 pediocin could inhibit the growth of the three kinds of indicator bacteria at 121 ℃， 15 min and pH 2-6， and had the strongest antibacterical effect on Listeria monocytogenes. The 2 pediocin had a wide spectrum of inhibition，which could inhibit not only Gram-positive bacteria such as Bacillus subtilis and Enterococcus faecalis， but also Gram-negative bacteria such as Salmonella enterica and Shigella castellani.