Semiconductor device

A semiconductor device includes a semiconductor element, first and second leads, and a sealing resin. The semiconductor element includes first and second electrodes. The first lead includes a mounting base having a main face to which the first electrode is bonded and a back face, and includes a first terminal connected to the first electrode. The second lead includes a second terminal connected to the second electrode. The sealing resin includes a main face and a back face opposite to each other, and includes an end face oriented in the protruding direction of the terminals. The back face of the mounting base is exposed from the back face of the resin. The sealing resin includes a groove formed in its back face and disposed between the back face of the mounting base and a boundary between the second terminal and the end face of the resin.