To prepare a cellulose acylate swollen liquid having excellent stability with time by using a nonchlorine based solvent in which a cellulose acylate is uniformly swollen, a cellulose acylate-uniformly dissolved solution, and furthermore, a cellulose acylate film having an excellent surface state.

A method for producing the cellulose acylate swollen liquid obtained by swelling the cellulose acylate in a solvent substantially constituted of the nonchlorine based solvent comprises a step of mixing the cellulose acylate in the solvent cooled at -70°C to -10°C, raising the temperature under stirring to swell the cellulose acylate, and further rendering the temperature at -100°C to -10°C.