The present invention relates to a flexible printed circuit board which has extremely high adhesion performance and on which very fine circuit patterns can be formed by etching, and to a method for producing the same. In the present invention, in the flexible printed circuit board wherein a copper thin film made of copper or an alloy containing primarily copper is directly formed on at least one side of a plastic film substrate, and copper is formed further on the copper thin film by the electrolytic plating method, the above-mentioned copper thin film has a two-layer structure in which a layer including at least a crystalline structure is formed on the surface side thereof, and the X-ray relative intensity ratio between crystal lattice plane indices (200)/(111) in the above-mentioned crystalline structure is 0.1 or less.