A wiring board includes a rectangular mount region surrounded by four sides circumscribed to pads located in an outer peripheral area among a plurality of pads arranged in a substantially matrix form, a corner pad close to a corner of the mount region, and a second via-conductor and a second corner via-conductor electrically connected to the corner pad via a first via-conductor and a first wiring conductor. In the wiring board, a distance in a plane direction between the second corner via-conductor and a center of the mount region is smaller than a distance in the plane direction between the corner pad and the center of the mount region.