Disclosed is a semiconductor package system comprising a substrate, a first semiconductor package on the substrate, and a heat radiation structure on the first semiconductor package. The heat radiation structure includes a first part on a top surface of the first semiconductor package and a second part connected to the first part. The second part has a bottom surface at a level lower than a level of the top surface of the first semiconductor package. A vent hole is provided between an edge region of the substrate and the first part of the heat radiation structure.