A method includes connecting in a wiring area a plurality of basic block patterns which include a plurality of track patterns extending to one direction and being disposed at a prescribed pitch in an intersection direction intersecting the one direction to generate a plurality of parallel wiring patterns, each of which includes the track patterns connected together; generating a wiring route running on a track pattern; cutting away a track pattern terminal end, on which no wiring route runs, out of track pattern terminal ends of a track pattern including a route end of the wiring route and an adjacent track pattern connected to a track pattern start end of the track pattern concerned; and generating a wiring pattern data including a block pattern identifier corresponding to a basic block pattern out of the basic block patterns in the wiring area and a layout position of the basic block pattern.