A cellulose acylate film is used in various photographic or optical elements because it is tough and has enough flame retardant properties. The cellulose acylate film is generally produced according to the solvent cast method, in which a solution (dope) containing a cellulose acylate dissolved in a solvent is cast on a support and then the solvent is evaporated to form the film. As the solvent, a chlorine-containing solvent comprising 70 wt. % or more of dichloromethane has been conventionally used. In consideration of environmental preservation, it has been studied to replace the chlorine-containing solvent with a non-chlorine-containing solvent such as acetone, methyl acetate, tetrahydrofuran, 1,3-dioxolane, nitromethane, 1,4-dioxolane, epichlorohydrin or N-methylpyrrolidone. However, some of these non-chlorine-containing solvents cannot give the solution (dope) in a sufficient concentration, and others have too high boiling points to dry. Further, even if the film is formed from the dope using the non-chlorine-containing solvent, peroxides are liable to precipitate in drying the film, so that there is a fear of explosion. For these reasons, the non-chlorine-containing solvents are not practically used.