A wiring substrate includes a silicon substrate, a through hole formed to penetrate the silicon substrate in a thickness direction, an insulating layer formed on both surfaces and side surfaces of the silicon substrate and an inner surface of the through hole, a penetration electrode formed in the through hole, a wiring layer formed on at least one surface of the silicon substrate and connected to the penetration electrode, and a metal wire terminal connected to the wiring layer and formed to extend from one surface of the silicon substrate to a side surface thereof. The metal wire terminal on the side surface of the electronic device is connected to the mounting substrate such that a substrate direction of the electronic device in which an electronic component is mounted on the wiring substrate intersects orthogonally with a substrate direction of the mounting substrate.