Provided is a trimming device 1 for a rectangular container configured to cut a rectangular container 100 along a trim line 100A, and includes: a die 10, which accommodates an outer periphery of the rectangular container 100, and is arranged along the trim line 100A on a lower side thereof; a punch 20 movable within a plane parallel to a bottom surface 101; a long-axis direction drive unit 61 configured to move the punch 20 along a long-axis direction of the rectangular container 100; a first short-axis direction drive unit 62, which is arranged on a proximal side of the long-axis direction drive unit 61, and is configured to move the punch 20 along a short-axis direction; and a second short-axis direction drive unit 63, which is arranged side by side with the first short-axis direction drive unit 62 along the long-axis direction on a distal side from the long-axis direction drive unit 61, and is configured to move the punch 20 along the short-axis direction of the rectangular container 100.