PURPOSE: To obtain a can lid-bagging device capable of enhancing a reliability in sealing a bag after can lids are bagged.

CONSTITUTION: In a can lid-bagging device 100 provided with an extruding cylinder 20 with a rod 21 abutted against a large number of can lids C placed on a can lid placing plate 10 and covered with a bag B for extruding the can lids C together with the bag B from the can lid-placing plate 10 to a bag sealing mount (not shown in the figure) of a bag sealing device for sealing the bag B, an expanding and shrinking body 25 that can expand and shrink by injecting and exhausting gas and can prevent the rotation of the bag B by coming into contact with the inner surface thereof in the expanded state is provided in the end part of the rod 21.