Lactic Acid Bacteria (LAB) isolated from several traditional fermented foods such as “tempehâ€, “tempoyak†and “tapai†were screened for the production of bacteriocin. One strain isolated from “tempeh†gives an inhibitory activity against several LAB. The strain was later identified as Lactobacillus plantarum BS2. Study shows that the inhibitory activity was not caused by hydrogen peroxide, organic acids or bacteriophage. The bacteriocin production was maximum after 10 hours of incubation with an activity of 200 AU/ml. The bacteriocin was found to be sensitive towards trypsin, a-chymotrypsin, b-chymotrypsin, a-amylase and lysozyme.