A wiring substrate includes a first insulating layer, a first conductor layer, a second insulating layer, a second conductor layer, a connection conductor, and a coating film. The first conductor layer includes a conductor pad and a wiring pattern such that the conductor pad is formed in contact with the connection conductor and that the wiring pattern is covered by the coating film, the conductor pad has a surface facing the second insulating layer and having first surface roughness higher than surface roughness of a surface of the wiring pattern, and the coating film has opening exposing a portion of the surface of the conductor pad from the coating film and having area larger than area of interface between the conductor pad and the connection conductor and that the connection conductor is formed on the portion of the surface of the conductor pad and is separated from the coating film.