A wiring substrate includes a substrate main body having a first main face and a second main face opposite the first main face; a resistor formed on the first main face; a plurality of first-main-face-side wiring layers which are each formed on the resistor and which each include a grounding metal layer formed of a metal having a resistance lower than that of the resistor and a conductor layer formed on the grounding metal layer; a second-main-face-side wiring layer formed on the second main face; and a via which is formed in the substrate main body and which establishes electrical connectivity between the first-main-face-side wiring layers and the second-main-face-side wiring layer. The wiring substrate further includes a conductive covering layer which covers an upper surface and substantially covers the side surfaces of each of the first-main-face-side wiring layers.