Support for forming hydrogen discharge film, and laminated hydrogen discharge film

The purpose of the present invention is to provide: a support for forming a hydrogen discharge film, which does not easily break when pressure is applied, and which exhibits excellent pressure-resistant airtightness; and a laminated hydrogen discharge film which uses said support. This support for forming a hydrogen discharge film is used in order to form a hydrogen discharge film including a metal layer, and is characterized in that: the support is a porous body; the porous body has an average pore size in a cross-sectional portion extending 4 µm in the thickness direction from the surface at the side where the hydrogen discharge film is formed of 30-100 nm; and the porous body has a maximum pore size in a cross-sectional portion extending 8 µm in the thickness direction from the surface at the side where the hydrogen discharge film is formed of not more than 2 µm.