An object of the present invention is to reduce processing time and manufacturing cost for a semiconductor device including a logic circuit. To accomplish the above object, an area (114) for forming a logic circuit includes a first area (114b, 170) which is subjected to optical proximity correction with predetermined accuracy, and a second area (114a, 180) which is subjected to optical proximity correction with accuracy lower than said predetermined accuracy. Especially, the first area (114b, 170) includes a gate interconnection line (172) which acts as a transistor, and the second area (114a, 180) includes a dummy layout pattern (182) which does not act as a transistor.