The present invention relates to a composition for oral cavity. The composition for oral cavity exerts an excellent effect of removing biofilm in the oral cavity by erythritol, and the effect of suppressing dentinal hyperesthesia is also excellent.That is, the present invention relates to a composition for oral cavity, which contains the following components (A), (B), (C) and (D):(A) Erythritol from 3% by mass to 33% by mass；(B) Potassium compounds；(C) N-amino acid or its alkali metal salt having a hydrocarbon group with 14 to 18 carbon atoms；(D) water； andThe mass ratio ((D)/(A)) of the content of the component (D) to the content of the component (A) is 1 or more and 10 or less.本發明係關於一種口腔用組合物，該口腔用組合物係藉由赤藻糖醇而發揮優異之口腔內生物膜之去除效果，並且象牙質感覺過敏抑制效果之發揮亦優異。即，本發明係關於一種口腔用組合物，其含有如下之成分(A)、(B)、(C)以及(D)：(A)3質量%以上33質量%以下之赤藻糖醇；(B)鉀化合物；(C)具有碳數14～18之烴基之N-醯基胺基酸或其鹼金屬鹽；(D)水；且成分(D)之含量與成分(A)之含量之質量比((D)/(A))為1以上10以下。
