The present application provides a semiconductor device including a first-conductivity type semiconductor substrate, a pillar structure portion formed on the first-conductivity type semiconductor substrate and formed of five semiconductor pillar layers arranged in one direction parallel to a main surface of the first-conductivity type semiconductor substrate, and isolation insulating portions formed on the first-conductivity type semiconductor substrate and sandwiching the pillar structure portion between the isolation insulating portions, wherein the pillar structure portion is formed of a first first-conductivity type pillar layer, a second first-conductivity type pillar layer and a third first-conductivity type pillar layer which sandwich the first first-conductivity type pillar layer, a first second-conductivity type pillar layer provided between the first first-conductivity type pillar layer and the second first-conductivity type pillar layer, and a second second-conductivity type pillar layer provided between the first first-conductivity type pillar layer and the third first-conductivity type pillar layer.