To provide a interlayer connected double-sided flash printed wiring board in which the surface is more smooth and which can have a precise circuit pattern, and a method of manufacturing thereof.

A conductive bump 11 is formed on at least a part of a circuit pattern of one foil board 9b of a first and a second foil boards 9a, 9b, in which circuit patterns 10 are formed on conductive foils of a foil board 9. A conductive foil 4 is adhered on the surface applied with an adhesive of a foil supporting board 8 comprising a fixed supporting base material 5 on an opposite surface to the adhesive-applied surface 2 of an adhesive-applied resin film 3 whose one surface is applied with a thermoplastic adhesive. These first and second foil board are arranged so that the respective circuit pattern 10 faces a insulating resin board 12 with the board 12 sandwiched, and the first and second foil boards are compressively laminated under heat, then both foil supporting board 8 is removed from the board 12.