An automatic backup pin arrangement system for a component mounting machine, comprising: a backup plate on which backup pins for holding a circuit board on which a component is mounted, from below are placed; and a first XY-robot configured to perform a component mounting operation of mounting the component on the circuit board and an automatic backup pin arrangement operation of automatically arranging the backup pins on the backup plate, wherein when performing the automatic backup pin arrangement operation, the first XY-robot is configured to use at least a part of a region of the backup plate not facing a lower surface of the circuit board, as a first stock area for storing the backup pins, pick up the backup pins stored in the first stock area, and automatically arrange the backup pins at positions of the backup plate designated in a production job, and when there is no free space where an unnecessary backup pin removed from the backup plate is retracted to the first stock area when a production job is switched for changing the arrangement of the backup pins, the first XY-robot is configured to use, as a first retraction area, at least a part of a region of the backup plate facing a lower surface of the circuit board, which does not interfere with a mounted component on a lower surface side of the circuit board, and retract the unnecessary backup pin that cannot be retracted to the first stock area to the first retraction area, characterized by a second XY-robot configured to perform a component mounting operation of mounting the component on the circuit board and an automatic backup pin arrangement operation of automatically arranging the backup pins on the backup plate, wherein when performing the automatic backup pin arrangement operation, the second XY-robot is configured to use at least a part of a region of the backup plate not facing a lower surface of the circuit board, as a second stock area for storing the backup pins, pick up the backup pins stored in the second stock area, and automatically arrange the backup pins at positions of the backup plate designated in a production job, and when there is no free space where an unnecessary backup pin removed from the backup plate is retracted to the second stock area when the production job is switched for changing the arrangement of the backup pins, the second XY-robot is configured to use, as a second retraction area, at least a part of the region of the backup plate facing a lower surface of the circuit board, which does not interfere with a mounted component on a lower surface side of the circuit board, and retract the unnecessary backup pin that cannot be retracted to the second stock area to the second retraction area. a backup plate on which backup pins for holding a circuit board on which a component is mounted, from below are placed; and a first XY-robot configured to perform a component mounting operation of mounting the component on the circuit board and an automatic backup pin arrangement operation of automatically arranging the backup pins on the backup plate, wherein when performing the automatic backup pin arrangement operation, the first XY-robot is configured to use at least a part of a region of the backup plate not facing a lower surface of the circuit board, as a first stock area for storing the backup pins, pick up the backup pins stored in the first stock area, and automatically arrange the backup pins at positions of the backup plate designated in a production job, and when there is no free space where an unnecessary backup pin removed from the backup plate is retracted to the first stock area when a production job is switched for changing the arrangement of the backup pins, the first XY-robot is configured to use, as a first retraction area, at least a part of a region of the backup plate facing a lower surface of the circuit board, which does not interfere with a mounted component on a lower surface side of the circuit board, and retract the unnecessary backup pin that cannot be retracted to the first stock area to the first retraction area, characterized by a second XY-robot configured to perform a component mounting operation of mounting the component on the circuit board and an automatic backup pin arrangement operation of automatically arranging the backup pins on the backup plate, wherein when performing the automatic backup pin arrangement operation, the second XY-robot is configured to use at least a part of a region of the backup plate not facing a lower surface of the circuit board, as a second stock area for storing the backup pins, pick up the backup pins stored in the second stock area, and automatically arrange the backup pins at positions of the backup plate designated in a production job, and when there is no free space where an unnecessary backup pin removed from the backup plate is retracted to the second stock area when the production job is switched for changing the arrangement of the backup pins, the second XY-robot is configured to use, as a second retraction area, at least a part of the region of the backup plate facing a lower surface of the circuit board, which does not interfere with a mounted component on a lower surface side of the circuit board, and retract the unnecessary backup pin that cannot be retracted to the second stock area to the second retraction area.