a laminated substrate includes : a core portion ; a first wiring portion configured to be stacked on the core portion and to include a first exposed surface formed by exposing at least part of a surface of the first wiring portion ; and a second wiring portion configured to be stacked on the first wiring portion , to include a second exposed surface formed by exposing at least part of a surface of the second wiring portion , and to have higher wiring density of conductor than the first wiring portion has , wherein the first exposed surface and the second exposed surface are provided respectively with a first pad and a second pad which are to be connected to electrodes of one semiconductor chip to be mounted on both the first exposed surface and the second exposed surface .