An object of the present invention is to provide a semiconductor device having a structure in which a resin hardly enters between an insert electrode and a nut at a time of resin sealing. The semiconductor device according to the present invention includes an insert electrode having an insert hole into which a bolt is inserted from outside, a nut which has a screw hole to be screwed with the bolt and is disposed on an inside of the insert electrode so that the screw hole is communicated with the insert hole, at least one semiconductor element being electrically connected to the insert electrode, and a resin sealing the inside of the insert electrode, the nut, and the at least one semiconductor element, wherein a burr is provided on an outer periphery of a direct contact surface of the nut being in direct contact with the insert electrode.