A printed wiring board includes multiple insulating layers laminated on each other and each including resin and core, the insulating layers having first-surface sides and second-surface sides on the opposite side, respectively, and including multiple first insulating and second insulating layers, multiple first-surface-side conductive layers formed on the first-surface sides of the first insulating layers, respectively, multiple second-surface-side conductive layers formed on the second-surface sides of the second insulating layers, respectively. The insulating layers include one or more insulating layer having the core positioned such that the core is shifted toward the first-surface side from the center in the thickness direction, the insulating layers include a central insulating layer positioned in the center of the insulating layers, and the first-surface-side and second-surface-side conductive layers are formed such that the first-surface side conductive layers have the total area which is set smaller than the total area of the second-surface-side conductive layers.