A method of manufacturing an electronic board includes: preparing a substrate in which substrate-side solder parts are provided on electrodes; preparing a mounting sheet having a resin layer in which a plurality of voids is formed in accordance with positions of the electrodes; attaching the resin layer to at least one of a first electronic component and the substrate so that interfaces of the first electronic component or the substrate-side solder parts are located inside the respective voids; causing the interfaces and the substrate-side solder parts to face each other at positions of the respective voids; and melting the substrate-side solder parts by heating to join the interfaces and the electrodes.