A component supply device comprises: a main body including a tape path which guides a component supply tape being sent in a longitudinal direction to a component supply position, and an introducing region which communicates with the tape path on a side opposite to the supply position in the longitudinal direction and introduces the supply tape into the tape path; and a tape position switching mechanism which switches the position of the supply tape in a vertical direction with respect to the tape path on the side opposite to the supply position. The tape position switching mechanism includes a supporter movable between a supporting position for supporting the supply tape from below and a non-supporting position separated from the supporting position in a width direction of the supply tape. The supporter releases the supply tape to move the supply tape downward from the supporting position to the non-supporting position.