A thin semiconductor device difficult to cause breakage of a semiconductor chip is disclosed. The semiconductor device comprises a sealing member, a semiconductor chip positioned within the sealing member, the semiconductor chip having a source electrode and a gate electrode on a first main surface thereof and a drain electrode on a second main surface as a back surface thereof, a first electrode plate (drain electrode plate) having an upper surface and a lower surface, a part of the upper surface of the first electrode plate being exposed to an upper surface of the sealing member and the lower surface portions of end portions of the first electrode plate being exposed to a lower surface of the sealing member, and second electrode plates (source electrode plate and gate electrode plate) each having a lower surface exposed to the lower surface of the sealing member and an upper surface positioned within the sealing member, wherein the drain electrode of the semiconductor chip is electrically connected to the drain electrode plate through an adhesive, one or plural stud type bump electrodes are formed by gold wire on the surface of each of the source electrode and gate electrode of the semiconductor chip, the bump electrode(s) being covered with an electrically conductive adhesive, the bump electrode(s) and the source and gate electrode plates are electrically connected with each other through the adhesive, and the bump electrode(s) and the source and gate electrode plates are not in contact with each other.