Disclosed herein is a semiconductor device, which comprises a semiconductor chip including, over one main surface thereof, first wirings, protective films formed so as to cover other portions excluding parts of the first wirings, flexible layers respectively formed on the protective films so as to exclude the parts of the first wirings, and second wirings having first portions respectively electrically connected to the parts of the first wirings, and second portions respectively drawn onto the flexible layers; a wiring board having third wirings over one main surface thereof; and an adhesive comprising a large number of conductive particles contained in an insulative resin, and wherein the semiconductor chip is bonded to the wiring board with the adhesive interposed therebetween in a state in which the one main surface thereof is face to face with the one main surface of the wiring board, and the second portions of the second wirings are respectively electrically connected to the third wirings with some of the large number of conductive particles interposed therebetween.