A wiring substrate includes an insulating layer, and a connection terminal formed on the insulating layer. The connection terminal includes a metal layer formed on the insulating layer and including an upper surface, a metal post formed on the upper surface of the metal layer and including upper and side surfaces, and a surface plating layer that covers the upper and side surfaces of the metal post. The metal layer includes a material that is inactive with respect to a material included in the surface plating layer. The metal layer has an upper surface edge part that is exposed at an outside from the side surface of the metal post in a plan view. The surface plating layer is formed to expose the upper surface edge part of the metal layer.