A semiconductor device, has a semiconductor substrate; a first insulating film which is disposed above the semiconductor substrate; a second insulating film which is disposed above the first insulating film; a wiring which is disposed in the first insulating film and has a plug connecting part; a plug which is disposed in the second insulating film and connected to the plug connecting part; a plurality of first dummy wirings which are disposed in a first area near the plug connecting part in the first insulating film; and a plurality of second dummy wirings which are disposed in a second area near the wiring excepting the plug connecting part in the first insulating film, and have at least either a width smaller than that of the first dummy wirings or a pattern coverage ratio larger than that of the first dummy wirings.