To provide a wiring board which can maintain the quality of a signal by suppressing reflection of a signal generated in the wiring board significantly, and to provide an electronic device having that wiring board.

The wiring board 11 comprises an insulating substrate 13, signal wiring 14, a plurality of reference potential wiring layers 15, and a plurality of reference potential wiring conductors 16 wherein the plurality of reference potential wiring layers 15 are arranged between adjoining insulating layers 13A. The reference potential wiring conductors 16 connect the reference potential wiring layers 15 opposing each other, the signal wiring 14 is provided to penetrate at least one insulating layer 13A and the first reference potential wiring conductor 16a has a cross-sectional area smaller than that of a second reference potential wiring conductor 16b in the direction perpendicular to the direction of lamination.