Component transfer device 10 is provided with two clamp mechanisms 11 and is detachably set on an empty slot of feeder set stand 36 of a component mounter. Each clamp mechanism 11 is configured to clamp a component between clamp members 12 and 13 facing each other in a horizontal direction, with the direction of the component clamped between clamp members 12 and 13 being rotated 90 degrees or 180 degrees by clamp member 13 of each clamp mechanism 11 on the pulley 34 side being rotated 90 degrees or 180 degrees by a rotation drive source. Next, the component clamped between clamp members 12 and 13 of each clamp mechanism 11 is picked up by component holding section 16 of a mounting head of a component mounter and mounted on a circuit board.
