A wiring board including a conductor post corresponding to high-density packaging is provided. The wiring board may comprise a conductor layer, a solder resist layer laminated on the conductor layer, and a conductor post that is electrically connected to a conductor layer which is disposed in a lower portion of a through-hole provided in the solder resist layer, wherein the solder resist layer comprises a thermosetting resin; the conductor post comprises tin, copper, or a solder; the conductor post includes a lower conductor post, which is located within the through-hole and includes an external side surface and a lower end surface, and an upper conductor post, which is located above the lower conductor post and is projected outside the solder resist layer; and at least a part of a lower end surface of the upper conductor post is brought into intimate contact with an outer surface of the solder resist layer.