A stacked semiconductor package includes a semiconductor package module including a plurality of semiconductor packages each of which has a first surface, a second surface facing away from the first surface, side surfaces connecting the first surface and the second surface and through-holes formed on the side surfaces to pass through the first surface and the second surface and which are stacked such that their through-holes vertically connect with one another, and adhesive members which are formed between the semiconductor packages and attach the semiconductor packages to one another, a main substrate supporting the semiconductor package module and formed, on a third surface thereof facing the semiconductor package module, with main connection pads which are aligned with the through-holes, and conductive connection members formed in the through-holes and electrically connecting the semiconductor packages with the main connection pads.