Although the two-dimensional coding can be read on both sides of the flexible printed circuit 2 shown in FIG. 3, the extension of the two-dimensional coding printing area 22 outward from the substrate 20 increases the area of the entire flexible printed circuit 2. As shown in FIG. 4, a direction of the plurality of cable wires 210 is set so that at least one of the plurality of cable wires 210 forms a bent portion on the wiring area 21. A blank area on the wiring area 21 where the bent portion is located is used as the two-dimensional coding printing area 22. By providing the transparent medium layer 220 on the two-dimensional coding printing area 22, a metal layer 222 is plated on the transparent medium layer 220, and the metal layer 222 is subjected to laser irradiation by a laser device to melt and remove the metal layer 222, thereby forming a double-sided two-dimensional coding image on the metal layer 222. Since the transparent medium layer 220 is below the two-dimensional coding printing area 22, the two-dimensional coding can be read from both the front and back sides. Moreover, the two-dimensional coding printing area 22 can be located in the wiring area 21 without having to increase the area of the flexible printed circuit 2.