A semiconductor device includes: a first semiconductor region of a first conductivity type disposed on the side of a first electrode; and a second semiconductor region having first pillar regions of the first conductivity type and second pillar regions of a second conductivity type, the first pillar regions and the second pillar regions being provided in paired state and alternately, in a device portion and a terminal portion surrounding the device portion, along a surface on the side of a second electrode disposed on the opposite side of the first semiconductor region from the first electrode. The semiconductor device further includes a lateral RESURF (reduced surface field) region of the second conductivity type disposed at a surface portion, on the opposite side from the first semiconductor region, of the second semiconductor region in the terminal portion.