PROBLEM TO BE SOLVED: To provide an oral composition having biofilm formation inhibitory action.SOLUTION: An oral composition comprises plant extract that is hot water extract of Brassica rapa var. perviridis, Brassica rapa var. laciniifolia, Brassica rapa var. laciniifolia subvar. oblanceolata, Raphanus sativus L. var. longipinnatus L.H.Bailey, Nasturtium officinale, Matteuccia struthiopteris (L.) Todaro, Aralia elata, or Mesembryanthemum crystallinum L.SELECTED DRAWING: Figure 2COPYRIGHT: (C)2017,JPO&INPIT【課題】バイオフィルム形成抑制作用を有する口腔用組成物の提供。【解決手段】小松菜、水菜、壬生菜、辛味大根、クレス、コゴミ、タラノキ、またはアイスプラントの熱水抽出物である植物抽出物を含有する口腔用組成物。【選択図】図2