Proposed is a mobile device case that accommodates or covers a substrate and an electronic element located on the substrate. The case includes: a case frame made of a high molecular material including a resin and having a cover part for accommodating or covering the substrate and protrusions protruding from the cover part in such a manner as to be extended close to the electronic element; and a metal coating layer formed by coating a metal on a surface of the case frame including the protrusions to improve electromagnetic shielding ability.