PROBLEM TO BE SOLVED: To provide a method for dismantlement of a packaging container by which dismantlement of a packaging container can be stably carried out with a simple structure.SOLUTION: A method for dismantlement of a packaging container, which is a method for dismantlement of a packaging container which is formed by folding a sheet material into a box shape, and overlapping and sealing end parts thereof, includes: a process in which a shank of the packaging container is crushed; a process in which the crushed packaging container is folded along a linear fragile portion formed in a width direction of the shank and is broken at least partially; and a process in which a part of the packaging container is separated from other parts at a broken site along the fragile portion.SELECTED DRAWING: Figure 4
