Lactic acid bacteria (LAB) occur naturally in meat. These bacteria produce antimicrobial substances such as bacteriocin. The present study is focused on isolation of LAB from meat. Bacteriocin is extracted from the isolated Lactococcus lactis and the antibacterial activity is evaluated against bacterial pathogens (E. coli and S. gallinarum) of poultry origin. The antimicrobial properties varies when different parameters are applied. The antimicrobial properties changes with the change in the pH, temperature, change in the concentration of ethanol, methanol, chloroform and SDS. When bacteriocin is treated with enzyme, it does not show any activity. The minimum inhibitory concentration (MIC) is also measured. This book shows the potential application of lactic acid bacteria in the poultry industry to protect the flocks against potential pathogens.