PURPOSE: To shield electromagnetic interfering waves from electric apparatus around a flexible wiring board by providing a through hole in an extension of a second insulating film, and openings larger than the opening area of the through hole in the extensions of first and third insulating films at positions corresponding to the through holes, respectively.

CONSTITUTION: In the extensions 12, 22, 32 of first, second, and third insulating films 10, 20, 30, the extensions are piled up on one another and so arranged that a through hole 24 and openings 14, 34 may be located concentrically. The openings 14, 34 formed in the first and third insulating films 10, 30 are so formed as to have an opening area larger than that of the through hole 24. This enables an extraction part 23 of a shield pattern 21 to be exposed to the third insulating film 30 side. Both longitudinal ends of a signal circuit pattern and the shield pattern 21 consisting of a plurality of signal lines 11 have joints to connect to connectors, etc.