A stretchable wiring board that includes a stretchable substrate having a first main surface with a first region, a second region adjacent the first region, and a third region adjacent the second region; a first stretchable wiring line on the first main surface and extending over the first region; an insulating layer extending over the first region and the second region; and a second stretchable wiring line extending over the first region, the second region, and the third region. At a position in the first region where the total thickness of the first stretchable wiring line, the insulating layer, and the second stretchable wiring line is the largest, the thicknesses of the first stretchable wiring line, the insulating layer, and the second stretchable wiring line satisfy a predetermined relationship with the thickness of the second stretchable wiring line at a boundary between the second region and the third region.