An object of the present disclosure is to provide an insulating film or dielectric film comprising a fluoropolymer and having electrical insulation and hardness. The present disclosure relates to an insulating film or dielectric film comprising a fluoropolymer, wherein the fluoropolymer comprises, as a main component, a monomer unit represented by formula (1): wherein R1 to R4 are each independently a fluorine atom, a fluoroalkyl group, or a fluoroalkoxy group.