A barrier-film forming apparatus that forms a barrier film on an inner face of a container having a concave or convex portion as a processing target, including: a dielectric member having a cavity sized to enclose the container, an external electrode covering an outer circumference of the dielectric member, an exhaust unit installed on an end face of the external electrode on a side where a mouth of the container is located, with an insulating member interposed therebetween, and depressurizing inside of the container through an exhaust pipe, an internal electrode inserted from a side of the exhaust pipe and also serving as a gas blowout unit that blows out medium gas for generating a barrier film into the container, and an electric-field applying unit that applies an electric field for generating exhaust between the external electrode and a ground electrode.