A QFP adapted to lowering the heat resistance and increasing the number of pins, and a method of producing the same. The QFP includes a heat-radiating metal plate having bumpers formed at the four corners thereof as a unitary structure, a semiconductor chip mounted on the heat-radiating metal plate, leads provided on the heat-radiating metal plate and surrounding the peripheries of the semiconductor chip, bonding wires for connecting the leads to the semiconductor chip, and a sealing resin member for sealing part of the semiconductor chip, inner leads of the leads, bonding wires and part of the heat-radiating metal plate. The tips of the bumpers integrally formed with the heat-radiating metal plate are positioned outside the tips of the outer leads that are protruding from the sealing resin member. In the QFP producing method, the heat-radiating metal plate having the bumpers and the lead frame having the leads are secured outside the sealing resin member.