According to one embodiment, a semiconductor device includes a drift region of a first conductivity type, a base region of a second conductivity type, a source region of the first conductivity type, a gate electrode in a trench shape, a contact region of the second conductivity type, a drain electrode, and a source electrode. The drift region is selectively provided in a drain layer of the first conductivity type from a surface of the drain layer to an inside of the drain layer. The base region is selectively provided in the drift region from a surface of the drift region to an inside of the drift region. The source region is selectively provided in the base region from a surface of the base region to an inside of the base region. The gate electrode penetrates from a part of the source region through the base region adjacent to the part of the source region to reach a part of the drift region in a direction substantially parallel to a major surface of the drain layer. The contact region is selectively provided on the surface of the drift region. The contact region contains an impurity having a concentration higher than an impurity concentration of the base region. The drain electrode is connected to the drain layer. The source electrode is connected to the source region and the contact region. The contact region extends from a side of the drain layer toward the drift region and does not contact the drain layer.