PURPOSE: To permit a smooth and accurate automatic insertion of an inner packaging sheet instead of the manual operation of a skilled worker, by automatically wrapping the inner packaging sheet around the outer periphery of a cylindrical drum under a negative pressure and disengaging the cylindrical drum alone from a container under a positive pressure with the inner packaging sheet engageably retained therein.

CONSTITUTION: The interior of a cylindrical drum 2 with a plurality of through holes 15 formed in the peripheral wall thereof is brought under a negative pressure so as to hold by suction an inner packaging sheet X around the outer peripheral surface thereof, resulting in an automatic wrapping operation instead of the manual operation. The cylindrical drum 2 with the inner packaging sheet X held around it is inserted into a container Y and the interior of the cylindrical drum is then brought back to a positive pressure so as to avoid the adhesion of the inner packaging sheet X to the cylindrical drum 2 upon disengagement thereof from the container Y, thereby not only saving trouble but also preventing the inner packaging sheet X from getting out of shape as compared with the manual removal operation.