To provide a solution for forming a double eyelid which enables extremely easy formation of a natural and ideal double eyelid without giving a displeased feeling or an uncomfortable feeling to a user, and a method for forming a double eyelid using the solution for forming a double eyelid. A solution for forming a double eyelid 1 according to the present invention is formed by dissolving, into a solvent having volatility, a fibrous material which forms a film 1a onto a skin 5a of an eyelid 5 and shrinks with vaporization of the solvent. By applying the solution 1, in a successive-curve form, over an imaginary line I forming a fold 5d of a double eyelid in the eyelid 5 onto which a user want to make a fold and vaporizing the solvent so as to shrink the film 1a, successive concaved groove-like constricted part 5c is formed on the imaginary line I and the fold 5d of a double eyelid along the constricted part 5c is formed.
