An electronic device comprising: a first cover constituting the front surface of the electric device; a second cover constituting the rear surface of the electric device; the first cover and the second cover being spaced from each other; a frame enclosing a space formed between the first cover and the second cover; a multilayer circuit board disposed in the space; wherein the multilayer circuit board comprises: an insulated metal layer made of a metal coated with an insulator having one surface attached to the second cover; an antenna device of a substrate structure having one surface attached to the insulated metal layer; a circuit board layer attached to the antenna device and configured to dispose at least one component at a surface opposite to a surface attached to the antenna device, wherein in the multilayer circuit board, the insulated metal layer and the antenna device have the same length in a longitudinal direction of the electronic device such that the insulated metal layer, the antenna device, and the circuit board layer are aligned without a step in a longitudinal direction of the electronic device on a first side, and the circuit board layer has a longer length in a longitudinal direction of the electronic device than that of the antenna device such that the insulated metal layer, the antenna device, and the circuit board layer are aligned with a step in a longitudinal direction of the electronic device on a second side, wherein: a second conductor is coupled to the first side in the longitudinal direction of the electronic device; and a first conductor is disposed on the circuit board layer and coupled to the second side, wherein, on the circuit board layer, the at least one component is disposed at a surface opposite to a surface on which the second conductor is disposed. a first cover constituting the front surface of the electric device; a second cover constituting the rear surface of the electric device; the first cover and the second cover being spaced from each other; a frame enclosing a space formed between the first cover and the second cover; a multilayer circuit board disposed in the space; wherein the multilayer circuit board comprises: an insulated metal layer made of a metal coated with an insulator having one surface attached to the second cover; an antenna device of a substrate structure having one surface attached to the insulated metal layer; a circuit board layer attached to the antenna device and configured to dispose at least one component at a surface opposite to a surface attached to the antenna device, wherein in the multilayer circuit board, an insulated metal layer made of a metal coated with an insulator having one surface attached to the second cover; an antenna device of a substrate structure having one surface attached to the insulated metal layer; a circuit board layer attached to the antenna device and configured to dispose at least one component at a surface opposite to a surface attached to the antenna device, wherein in the multilayer circuit board, the insulated metal layer and the antenna device have the same length in a longitudinal direction of the electronic device such that the insulated metal layer, the antenna device, and the circuit board layer are aligned without a step in a longitudinal direction of the electronic device on a first side, and the circuit board layer has a longer length in a longitudinal direction of the electronic device than that of the antenna device such that the insulated metal layer, the antenna device, and the circuit board layer are aligned with a step in a longitudinal direction of the electronic device on a second side, wherein: a second conductor is coupled to the first side in the longitudinal direction of the electronic device; and a first conductor is disposed on the circuit board layer and coupled to the second side, wherein, on the circuit board layer, the at least one component is disposed at a surface opposite to a surface on which the second conductor is disposed. a second conductor is coupled to the first side in the longitudinal direction of the electronic device; and a first conductor is disposed on the circuit board layer and coupled to the second side, wherein, on the circuit board layer, the at least one component is disposed at a surface opposite to a surface on which the second conductor is disposed.