PROBLEM TO BE SOLVED: To provide a composition for oral cavity and a foul-breath inhibitor having a high deodorization effect on foul breath, remarkably improved in sustainability of the effect and having low stimulation and mild sense of use.SOLUTION: There are provided the composition for oral cavity containing (A) a cyclodextrin and (B) Na and/or K salts of a polyglutamic acid, and the foul-breath inhibitor consisting of (A) a cyclodextrin and (B) Na and/or K salts of a polyglutamic acid.