An electronic device is provided with an electronic component having a base material and a terminal electrode formed on a first surface of the base material, and a circuit substrate in which a pad for mounting the electronic component is formed on a first surface. A hole for light transmission is formed in the pad, and the pad and the terminal electrode are electrically and mechanically connected to each other with a cured product of optical firing paste obtained by receiving light from a second surface that is a surface opposite to the first surface of the circuit substrate.