(A) water-soluble fluorine-containing compound, (B) α-olefin sulfonate, (C) hydroxyethylcellulose dimethyldiallylammonium salt, the content of (A) component is more than 900ppm as a fluorine ion, (B) component It provides a composition for oral cavity which is characterized in that the content is 0.1 to 1% by mass, has excellent retention of fluorine ions on the tooth surface, and is suitable for the prevention or suppression of caries.(A)수용성 불소 함유 화합물, (B)α-올레핀술폰산염, (C)히드록시에틸셀룰로오스디메틸디알릴암모늄염을 함유하고, (A)성분의 함유량이 불소 이온으로서 900ppm 이상, (B)성분의 함유량이 0.1∼1질량%인 것을 특징으로 하고, 불소 이온의 치면에의 체류성이 우수하고, 우식의 예방 또는 억제용으로서 바람직한 구강용 조성물을 제공한다.
