A semiconductor device includes a semiconductor element in the form of a flat plate that has opposed first and second surfaces, an insulating layer that covers control wiring located on the first surface side of the semiconductor element, a metal block that is bonded to the first surface side of the semiconductor element via a solder layer, and a protective film that is formed between the metal block and the insulating layer, the protective film having a hardness equal to or greater than a hardness of the metal block. When viewed from the first surface side, the protective film is formed in an area at least including a position where an edge portion of the metal block and the control wiring cross each other.