The present invention relates to a novel brominated furanone derivative, a method for preparing the same, and a pharmaceutical composition containing the same as an active ingredient, wherein the novel brominated furanone derivative or a pharmaceutically acceptable 5 salt thereof according to the present invention exhibits a quorum sensing inhibitory activity of bacteria and also can effectively inhibit the formation of biofilm of bacteria, and thus can be used as a pharmaceutical composition containing the same as an active ingredient, thereby having an effect of being useful, 10 for example, for periodontal diseases such as gingivitis and periodontitis, oral diseases, and the like.