A wiring substrate includes a first wiring layer including a first wiring part having a first wiring interval and a second wiring part having a second wiring interval wider than the first wiring interval, a metal plane layer formed on a portion of a first insulation layer formed on the first wiring layer, the first wiring part being located below the portion, a second insulation layer formed on the first insulation layer and the metal plane layer and having a first via hole and a second via hole, a second wiring layer formed on the second insulation layer and connected to the first wiring layer via a first via conductor formed in the first via hole, and a third wiring layer formed on the second insulation layer and connected to the metal plane layer via a second via conductor formed in the second via hole.