A semiconductor device includes a semiconductor substrate, a first insulating layer laminated on the semiconductor substrate, a first metal wiring pattern embedded in a wire-forming region of the first insulating layer, a second insulating layer laminated on the first insulating layer, a second metal wiring pattern embedded in a wire-forming region of the second insulating layer and first dummy metal patterns embedded each in a wire-opposed region opposing to the wire-forming region of the second insulating layer and in a non-wire-opposed region opposing to a non-wire-forming region other than the wire-forming region of the second insulating layer, the wire-opposed region and the non-wire-opposed region each in a non-wire-forming region other than the wire-forming region of the first insulating layer.