Abstract: The present invention comprises a novel strain of Lactobacillus johnsonni FERM BP-2680, a lactic acid bacteria preparation using the Lactobacillus johnsonni FERM BP-2680, and a process of manufacturing the lactic acid bacteria preparation. The process includes the steps of inoculating the Lactobacillus johnsonni FERM BP-2680 into a medium containing fermentable sugar as a major carbon source, cultivating and proliferating under cultivation conditions adapted to anaerobes or facultative anaerobes, and further isolating the Lactobacillus johnsonni from the medium and drying the isolated Lactobacillus johnsonni with a protective agent to produce the lactic acid bacteria preparation. Optionally a bulking agent may be added to control cell concentration of the preparation. The preparation containing Lactobacillus johnsonni FERM BP-2680 is used to suppress harmful bacteria in the digestive tract of mammals.