A manufacturing process for an embedded semiconductor device is provided. In the manufacturing process, at least one insulation layer and a substrate are stacked to each other, and a third metal layer is laminated on the insulation layer to embed a semiconductor device in the insulation layer. The substrate has a base, a first circuit layer, a second circuit layer, and at least a first conductive structure passing through the base and electrically connected to the first circuit layer and the second circuit layer. In addition, the third metal layer is patterned to form a third circuit layer having a plurality of third pads.