There are provided an electronic device mounting substrate and an electronic apparatus which are capable of miniaturization. An electronic device mounting substrate includes: an insulating base including a frame section; an electrode pad disposed on an upper surface of the frame section; and a first conductor disposed on a side surface of the frame section, the first conductor being electrically connected to the electrode pad, the electrode pad extending over a side surface of the first conductor from the upper surface of the frame section. By suppressing separation of the first conductor from the insulating base by means of the electrode pad, disconnection at the first conductor can be suppressed.