It is an object of the present invention to provide a printed circuit board that can be housed at high density in the enclosures of electronic devices. The printed circuit board (40) according to a preferred embodiment of the invention has a construction with a substrate (1), a conductor (7) formed in a flexible region (36) and conductors (8,9) formed in non-flexible regions (46). The conductor (7) formed in the flexible region (36) has a total thickness of 1-30 μm, and the conductors (8,9) formed in the non-flexible regions (46) have a total thickness of 30-150 μm.