Disclosed is a semiconductor device which has a wiring structure including a small-width wiring connected to a large-width wiring through a connection hole or holes formed in an inter-layer insulation film and in which reliability of wiring can be enhanced by regulating the number of the connection hole or holes and the location(s) of the connection hole or hole. The semiconductor device includes first wirings (21), (22), an inter-layer insulation film (not shown) covering the first wirings (21), (22), second wirings (31), (33) connected to the first wirings (21), (22) through the connection holes formed in the inter-layer insulation film, the first wirings (21), (22) being formed to be larger in width than the second wirings (31), (33), wherein a plurality of the connection holes (41), (42) and connection holes (43) to (45) are provided, and the plurality of the connection holes (41), (42), (43) to (45) are disposed at intervals between the connection holes (41), (42) and between the connection holes (43) to (45) within the range of from 1 to 18 times the connection hole diameter.