PROBLEM TO BE SOLVED: To provide a bathing agent composition which generates fine bubbles on a bath water surface, can retain the bubbles satisfactorily, heightens a feeling of the bubbles to skin, can maintain moisture in skin even after bathing.SOLUTION: A bathing agent composition comprises (A) organic acid, (B) carbonate, (C) a nonionic surfactant with HLB as a whole of 11 or more, and (D) a thickening agent which is a cellulose derivative. The mass ratio of the component (C) to the component (D) ((C)/(D)) is 200 or less.