The present invention is a formed body, a production method thereof, an electronic device member comprising the formed body, and an electronic device comprising the electronic device member, the formed body being formed by sequentially layering a base layer, a primer layer and a gas barrier layer, characterized in that: the primer layer is configured from a material containing at least carbon atoms, oxygen atoms and silicon atoms, and in which the binding energy peak position of the 2p electron orbital in the silicon atom is 101.5 to 104 eV in the X-ray photoelectron spectroscopy (XPS) measurement; and the gas barrier layer is configured from a material containing (I) a layer obtained by implanting an ion in a polymer layer containing at least one type selected from a group comprising a polysilazane-based compound, a polyorganosiloxane-based compound, a polycarbosilane-based compound and a polysilane-based compound, or (II) at least oxygen atoms and silicon atoms, the proportion of oxygen atoms present being 60 to 75%, the proportion of nitrogen atoms present being 0 to 10%, and the proportion of silicon atoms present being 25 to 35%, with respect to the entire amount of oxygen atoms, nitrogen atoms and silicon atoms in the surface portion, and the film density in the surface layer portion being 2.4 to 4.0 g / cm3.