A wiring board includes a first insulation layer, first conductive patterns formed on the first insulation layer, a second insulation layer formed on the first insulation layer and the first conductive patterns and having an opening portion, a wiring structure accommodated in the opening portion of the second insulation layer and including an insulation layer and conductive patterns on the insulation layer, second conductive patterns formed on the second insulation layer; and a via conductor formed in the second insulation layer and connecting one of the first conductive patterns and one of the second conductive patterns.