A semiconductor package according to an embodiment of the present invention includes: a heat sink board including an insulated board and a first metal layer formed on the insulated board; at least one semiconductor chip placed on the first metal layer; a plurality of lead frames connected to the semiconductor chips used to electrically connect the semiconductor chips to the outside; and a package housing partially covering the heat sink board, wherein both end parts of the insulated board are projected further than both end parts of the first metal layer.