To manufacture a stack semiconductor package, a board mold covers a first semiconductor. The board mold includes a first face and a second face opposite to the first face. An active surface of the first semiconductor faces the second face. A first opening is formed in the board mold from the second surface. The first opening is disposed on the first semiconductor. A second opening penetrates the board mold from the first surface. A conductive metal layer fills the first and the second openings using an electroless plating method. A plurality of semiconductor devices is stacked on the first face of the board mold.