A semiconductor device includes a conductivity type drain layer, a conductivity type drift layer, conductivity type base regions located in an upper surface of the drift layer, a conductivity type source region which is disposed inside each of the base regions and is spaced apart from the periphery of the base region, and a channel region is formed between the source region and the periphery of the base region. The semiconductor device further includes a gate insulating layer covering the channel region, a gate electrode which is located on the gate insulating layer and faces the channel region, a plurality of conductivity type column regions, each extends from the plurality of base regions to the drain layer in the drift layer, a trap level forming region in the drift layer, a drain electrode electrically connected to the drain layer, and a source electrode electrically connected to the source region.