To provide a cation-modified cellulose derivative-containing composition capable of retaining stable quality and having high commercial value without causing separation of a liquid dispersion medium with passage of time.

This cation-modified cellulose derivative-containing composition features comprising (A) cation-modified cellulose derivative, (B) water and (C) a lower alcohol as main ingredients and containing the ingredient A in a weight ratio of {ingredient A/(ingredients A+B+C)} of 0.5-0.7.