An electronic component mounting device, including: a board conveyance device which conveys and positions a board on which an electronic component is mounted; a mounting device which positions and mounts the electronic component to a mounting position of the board; a loading device which picks up multiple engaged members (clips), and positions and loads the engaged members to a loading position of the board; and a placing device which picks up a cover component that covers the mounted electronic component and that is provided with an engaging portion at a predetermined position, and positions and places the cover component to a position such that the engaging portion corresponds to the engaged member.