A semiconductor device includes: a first conductivity type semiconductor substrate; and a plurality of second conductivity type semiconductor regions, the respective second conductivity type semiconductor regions being embedded in a plurality of stripe shaped trenches formed in the semiconductor substrate so that the respective second conductivity type semiconductor regions are extended in the row direction or the column direction in parallel with a first principal surface of the semiconductor substrate and are spaced in a fixed gap mutually. The semiconductor substrate and the plurality of the semiconductor regions are depleted by a depletion layer extended in the direction in parallel to the first principal surface from a plurality of pn junction interfaces, and the respective pn junction interfaces are formed between the semiconductor substrate and the plurality of the semiconductor regions.