Package substrate and manufacturing method thereof

The invention provides a manufacturing method of a packaging substrate. The manufacturing method comprises the following steps: providing a carrier; a first circuit substrate is formed on the surface of the carrier, the first circuit substrate comprises a first circuit area and a first waste area, and the first circuit area and the first waste area are separated through a first groove penetrating through the first circuit substrate in the thickness direction; arranging a first adhesive layer corresponding to the first waste area on one side of the first circuit substrate, wherein the first adhesive layer covers the first groove and partially extends to the first circuit area; forming a second circuit substrate on the surface of the first circuit substrate; the second circuit substrate comprises a first outer side circuit layer; and removing the first waste material area and the carrier and at least removing a part of the first adhesive layer corresponding to the first waste material area to form a first groov