A semiconductor device having a semiconductor module that includes a first conductor layer and a second conductor layer facing each other, a group of semiconductor elements that are formed between the first and second conductor layers, and are connected to the second conductor layer respectively via a group of conductor blocks, and a circuit board having one end portion thereof located in a space between the semiconductor elements and the second conductor layer. Each semiconductor element includes first and second main electrodes respectively formed on first and second main surfaces thereof, and a control electrode that is formed on the second main surface. The first main electrode is electrically connected to the first conductor layer. The second main electrode is electrically connected to the second conductor layer via the respective conductor block. The circuit board includes a first wiring layer electrically connected to the control electrodes of the semiconductor elements.