A packaging substrate having a through-holed interposer embedded therein is provided, which includes: a molding layer having opposite first and second surfaces; a through-holed interposer embedded in the molding layer and flush with the second surface; a redistribution-layer structure embedded in the molding layer and disposed on the through-holed interposer and having a plurality of electrode pads exposed from the first surface of the molding layer; and a built-up structure disposed on the second surface of the molding layer and electrically connected to the through-holed interposer. By embedding the through-holed interposer in the molding layer and forming the built-up structure on the second surface of the molding layer, the present invention eliminates the need of a core board and reduces the thickness of the overall structure. Further, since the through-holed interposer has a CIE close to or the same as that of a silicon wafer, the structural reliability during thermal cycle testing is improved.