A semiconductor package comprising a package substrate that extends in a first direction and a second direction perpendicular to the first direction, a plurality of logic dies and a memory stack structure on the package substrate, and an interposer substrate mounted in the package substrate. The memory stack structure vertically overlaps the interposer substrate. Each of the logic dies includes a first part that is horizontally offset from the interposer substrate and a second part that vertically overlaps the interposer substrate. The interposer substrate includes an interlayer dielectric layer and a plurality of wiring lines in the interlayer dielectric layer. The memory stack structure is electrically connected to at least one of the logic dies through the wiring lines of the interposer substrate.