A packaging substrate and a semiconductor package each include: a metal board having a first surface and a second surface opposite to the first surface, wherein the first surface has a plurality of first openings for defining a first core circuit layer therebetween, the second surface has a plurality of second openings for defining a second core circuit layer therebetween, each of the first and second openings has a wide outer portion and a narrow inner portion, and the inner portion of each of the second openings is in communication with the inner portion of a corresponding one of the first openings; a first encapsulant formed in the first openings; a second encapsulant formed in the second openings; and a surface circuit layer formed on the first encapsulant and the first core circuit layer.