To perform opening by pressing the end face of a pack to a cutter part, making a notch and performing tearing up from there.

For a pack cutter main body 1, the cutter part 3 and a sucker 2 are integrated and it is fixed and placed to the stable vertical surface of the glass door of a cupboard or the like and a refrigerator or the like in a kitchen with the sucker 2. The end face of the pack 6 sealed by a plastic film is pressed from the arrow 5 of a notching direction to the cutter part 3, a notched part 8 is made on the end face, tearing up is performed from the notched part 8 and the pack 6 sealed with the plastic film is opened.