To provide a multipiece wiring board having high reliability of electric connection with an electronic part and having high productivity.

The multipiece wiring board is provided with a mother board consisting of laminating a plurality of insulating layers, forming a plurality of vertical and horizontal arrays of wiring board areas 4 on the center and forming a dummy area 6 on the outer peripheral part, wiring conductors 3 formed in respective wiring board areas, conductive patterns 5 formed in the dummy area 6, 1st insulating coat layers 7 each of which covers part of the surface of each wiring conductor 3, and 2nd insulating coat layers 8 each of which is formed on the inside of the surface of each conductor pattern 5 so that the outer peripheral edge forms a fixed interval from the outer peripheral edge of the conductor pattern 5 over the whole periphery.