To improve a reflow characteristic and realize leadlessness. A semiconductor device comprises a cross die pad which supports a semiconductor chip and in which an area of the region joined to the semiconductor chip is smaller than that of the outer size thereof being smaller than the rear surface of the semiconductor chip; wires connected to pads of the semiconductor chip; a plurality of inner leads which are arranged around the semiconductor chip and in which a silver plating layer is formed at a wire bonding area; molding resin for resin sealing the semiconductor chip; a plurality of outer leads exposed from the molding resin and in which a lead-free metallic layer is formed on a contact surface, wherein the flat surface size of the molding resin is formed to be equal to or less than 28 mm28 mm and the thickness thereof is formed to be 1.4 mm or less, and thereby it is possible to improve a reflow characteristic and realize leadlessness.