A semiconductor device includes a semiconductor chip, an electrode electrically connected to the semiconductor chip, the electrode including a looped portion, a cylindrical electrode including a main portion having a screw thread formed therein and a narrow portion continuous with the main portion, the narrow portion having a smaller width than the main portion, the cylindrical electrode being electrically connected to the electrode by the narrow portion being inserted into the looped portion, and a case for the semiconductor chip and the electrode, the case contacting the main portion while causing the screw thread and a connecting portion between the looped portion and the cylindrical electrode to be exposed.