A semiconductor device includes a semiconductor substrate having a main surface; an element separation film formed on the main surface in an element separation area and extending in a first direction; and a semiconductor element formed on the main surface in an active area and arranged in a second direction perpendicular to the first direction. The semiconductor element includes a metal silicide film. The metal silicide film includes a first portion adjacent to the element separation film. The semiconductor device further includes an interlayer insulation film formed on the main surface of the semiconductor substrate; a wiring portion formed on the interlayer insulation film; and a conductive plug formed in the interlayer insulation film for electrically connecting the semiconductor elements and the wiring portion. The conductive plug is situated on the element separation film and the metal silicide film.