A stack package includes a first semiconductor chip possessing a first size and one or more second semiconductor chips possessing a second size greater than the first size. The first semiconductor chip has a first surface on which bonding pads are disposed, a second surface which faces away from the first surface, and first through-electrodes which pass through the first surface and the second surface. The one or more second semiconductor chips are stacked on the second surface of the first semiconductor chip and have second through-electrodes which are electrically connected to the first through-electrodes. A molding part abuts one or more side surfaces of the first semiconductor chip such that a total size including the first size and a size of the molding part is equal to or greater than the second size.