A film production method for producing a layer containing a metal oxide, the film production method including: a heating step of heating a metal foil containing a first metal by bringing a part of the metal foil into contact with at least one heat generator; a first contact step of letting first gas containing a second metal to be in contact with both surfaces of the metal foil in a state where the part of the metal foil is supported; and a second contact step of letting second gas containing an oxidant to be in contact with the both surfaces of the metal foil in a state where the part of the metal foil is supported.