A high reliability semiconductor device is provided which can prevent electromigration due to the deposition of metal ions originating from wires. The device includes: a flexible wiring board 11 including a base film 1 and multiple wires 9; a semiconductor chip 5 mounted to the flexible wiring board 11; and a sealing resin 6 disposed between the flexible wiring board 11 and the semiconductor chip 5 so as to at least partially in contact with the wires 9. The sealing resin 6 contains a metal ion binder mixed thereto.