Disclosed herein is a printed circuit board having an improved structure of a dummy part to improve warpage strength of the printed circuit board, the printed circuit board including: a plurality of insulating layers built-up therein, the plurality of insulating layers including copper clad layers; and a product zone and a dummy zone formed at a central part and along an edge part of the insulating layers, respectively, wherein the copper clad layers included in each insulating layer are arranged in the dummy zone at predetermined intervals in a longitudinal direction.