An electronic component mounting board, including: a substrate base made of a flat-plate-like elastic body, the substrate base having a plurality of through-holes in a manner spaced a predetermined distance apart from each other; conductive members, each of which has a main unit portion filled in the through-hole, the main unit portion having a first protrusion portion and a second protrusion portion respectively on a first end and a second end thereof, with the first protrusion portion arranged so as to protrude from a first surface of the substrate base and the second protrusion portion arranged so as to protrude from a second surface of the substrate base; a flexible substrate that is arranged on the first surface of the substrate base and that has first opening portions for penetration of the first protrusion portions; and a plurality of oval electrodes arranged on the substrate, each of which has a second opening portion for penetration of the first protrusion portion, in which the electrodes are arranged in a manner spaced apart from each other, and each of the second opening portions is formed on a first end side of each of the electrodes.