According to an embodiment, provided is a semiconductor device includes an insulating substrate; a first main terminal; a second main terminal; an output terminal; a first metal layer connected to the first main terminal; a second metal layer connected to the second main terminal; a third metal layer disposed between the first metal layer and the second metal layer and connected to the output terminal; a first semiconductor chip and a second semiconductor chip provided on the first metal layer; and a third semiconductor chip and a fourth semiconductor chip provided on the third metal layer. The second metal layer includes a first slit. Alternatively, the third metal layer includes a second slit.