In order to isolate the antibacterial bacteriocin-producing bacteria against Listeria monocytogenes, one of noxious and prevalent food-poisoning bacterium, 117 strains of indigenous ferment bacteria were isolated from Korean traditional fermented soybean paste (Doenjang) in Korea. Among the isolated strains, 4 isolates inhibited the growth of L. monocytogenes. Strain J4, showing the strongest inhibition activity against L. monocytogenes, was identified as a Bacillus amyloliquefaciens by 16S rDNA sequencing. The strain had a broad spectrum of antibacterial activity against various food-borne pathogens such as Micrococcus luteus, Vibrio parahaemolyticus, and Staphylococcus aureus besides L. monocytogenes. The bacteriocin $_{J4}$ was purified by 60% ammonium sulfate precipitation, carboxymethyl (CM)-Sephadex column chromatography, and Sephadex G-100 gel filtration. The purified bacteriocin $_{J4}$ was estimated to be 39 kDa molecular weight by tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Bacterocin $_{J4}$ had antimicrobial activity in a wide pH range (2.0-12.0) and was heat-stable at $80^{circ}C$ for 20 min, but the activity of bacterocin was inactivated by heating at $100^{circ}C$ for 15 min. The antimicrobial activity of the bacteriocin $_{J4}$ was completely abolished by treatment with proteolytic enzymes such as protease (type I and IX), papain, trypsin, proteinase K, and pepsin, but not when treated with ${alpha}$-amylase, ${alpha}$-glucosidase, and ${eta}$-glucosidase. The encoding gene of the bacteriocin $_{J4}$ was included in chromosomal DNA, not plasmid. The bacteriocin $_{J4}$ had a bacteriolytic mechanism, resulting in cell wall degradation of L. monocytogenes.