To provide a conductive-film polymer dispersion that is stabilized with suppressed production of sulfate ions as a by-product.

A composition used as a conductive-film polymer dispersion includes: at least one amine compound selected from the group consisting of aromatic primary amine compounds, linear aliphatic primary amines having 6-12 carbon atoms, linear aliphatic secondary amines having 4-10 carbon atoms, alicyclic primary amines, alicyclic secondary amines, and heterocyclic amines; polythiophene; poly(styrenesulfonate); and water.