The invention aims to provide a method by which a solution of polyimide can be easily obtained. Further, the invention aims to provide a fluorinated polyimide solution by which fluorinated polyimide excellent especially as an optical material and an electronic functional material can easily be produced. The production method of the soluble polyimide solution according to invention is characterized by mixing a mixture containing a polyamide acid, a cyclodehydration reagent, and a solvent by a rotation-revolution mixing method. Further, the fluorinated polyimide solution of the invention is a solution of polyimide defined by the following formula (II): wherein, X and Y independently represent divalent organic groups; Z represents chlorine atom, bromine atom, or iodine atom; p represents an integer of 1 to 3; q represents an integer of 0 to 2; and p+q=3.