PROBLEM TO BE SOLVED: To provide a polymer film in which fluctuation of Re and Rth accompanying humidity change of a use environment is reduced.SOLUTION: The polymer film contains at least one of a compound represented by general formula (1) or a hydrate, a solvate, or a salt thereof (in formula, Y represents a methine group or a nitrogen atom; each of Q, Q, and Qrepresents a single bond or a divalent linking group; each of R, R, and Rrepresents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a cyano group, a halogen group, or a heterocyclic group; Xrepresents a single bond or a divalent linking group; Xrepresents a single bond or a predetermined divalent linking group; each of Rand Rrepresents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a heterocyclic group; however, compounds etc. in which either -Q-Ror -N(XR)XRis -NHare excluded).
