A semiconductor package system comprising: a substrate; a first semiconductor package on the substrate; a second semiconductor package on the substrate; a first passive element on the substrate; a heat dissipation structure on the first semiconductor package, the second semiconductor package, and the first passive element; and a first heat conduction layer between the first semiconductor package and the heat dissipation structure, a sum of a height of the first semiconductor package and a thickness of the first heat conduction layer being greater than a height of the first passive element, and the height of the first semiconductor package being greater than a height of the second semiconductor package, and further comprising: a ground pattern on an upper surface of the substrate, wherein the ground pattern comprises a ground pad for receiving a ground voltage; and a conductive adhesive pattern between the ground pattern and a leg portion of the heat dissipation structure, wherein the heat dissipation structure includes a body portion and the leg portion, the body portion extends in parallel to the upper surface of the substrate, the leg portion is integral with the body portion, the leg portion is between the substrate and the body portion, and the heat dissipation structure is electrically connected to the ground pattern through the conductive adhesive pattern, wherein a thickness of the first heat conduction layer is less than a thickness of the conductive adhesive pattern. a substrate; a first semiconductor package on the substrate; a second semiconductor package on the substrate; a first passive element on the substrate; a heat dissipation structure on the first semiconductor package, the second semiconductor package, and the first passive element; and a first heat conduction layer between the first semiconductor package and the heat dissipation structure, a sum of a height of the first semiconductor package and a thickness of the first heat conduction layer being greater than a height of the first passive element, and the height of the first semiconductor package being greater than a height of the second semiconductor package, and further comprising: a ground pattern on an upper surface of the substrate, wherein the ground pattern comprises a ground pad for receiving a ground voltage; and a conductive adhesive pattern between the ground pattern and a leg portion of the heat dissipation structure, wherein the heat dissipation structure includes a body portion and the leg portion, the body portion extends in parallel to the upper surface of the substrate, the leg portion is integral with the body portion, the leg portion is between the substrate and the body portion, and the heat dissipation structure is electrically connected to the ground pattern through the conductive adhesive pattern, wherein a thickness of the first heat conduction layer is less than a thickness of the conductive adhesive pattern. a ground pattern on an upper surface of the substrate, wherein the ground pattern comprises a ground pad for receiving a ground voltage; and a conductive adhesive pattern between the ground pattern and a leg portion of the heat dissipation structure, wherein the heat dissipation structure includes a body portion and the leg portion, the body portion extends in parallel to the upper surface of the substrate, the leg portion is integral with the body portion, the leg portion is between the substrate and the body portion, and the heat dissipation structure is electrically connected to the ground pattern through the conductive adhesive pattern, wherein a thickness of the first heat conduction layer is less than a thickness of the conductive adhesive pattern.