A wiring board including a build-up circuit layer, a patterned conductive layer, first and second adhesion promoting material layers and first and second solder mask layers is provided. The build-up circuit layer has a first surface and a second surface opposite thereto. The patterned conductive layer is disposed on the second surface. The first adhesion promoting material layer is disposed on the first surface and includes at least one first opening. The second adhesion promoting material layer is disposed on the second surface and the patterned conductive layer, and includes at least one second opening. The first solder mask layer is disposed on the first adhesion promoting material layer and includes at least one third opening provided corresponding to the first opening. The second solder mask layer is disposed on the second adhesion promoting material layer and includes at least one fourth opening provided corresponding to the second opening.