A wiring board with a built-in electronic component includes a substrate having a cavity, an electronic component accommodated in the cavity, a conductive layer formed on the substrate and extending over the electronic component in the cavity, and a solder-resist layer formed on the conductive layer and having first and second openings such that the first openings are forming first pads including the conductive layer exposed by the first openings and that the second openings are forming second pads including the conductive layer exposed by the second openings. The second pads include portions of the conductive layer formed directly over the electronic component, respectively, and connected to the electronic component, the first pads include portions of the conductive layer formed on outer side with respect to the electronic component, respectively, and each second opening has an opening diameter which is formed smaller than an opening diameter of each first opening.