A component mounting apparatus includes a plurality of transport conveyor units that are arranged in parallel and transports boards, each transport conveyer unit including a pair of transport rails of a fixed rail and a movable rail, a fixed side transport motor that drives a fixed side transport belt provide on the fixed rail, and a movable side transport motor that drives a movable side transport belt provide on the movable rail. The fixed side transport motor is provided on a side surface of the fixed rail that faces the movable rail, and the movable side transport motor is provided on a side surface of the movable rail that faces the fixed rail. The fixed side transport motor and the movable side transport motor are arranged so as not to interfere with each other when the distance between the pair of transport rails is changed.