A cardboard box dividing device for cutting and dividing, along a width direction (Db) intersecting with a transport direction (Da), a connected cardboard box laminate in which a plurality of connected cardboard box bodies continuous along the transport direction (Da) are stacked in a thickness direction (Dc), the cardboard box dividing device comprising: a lower conveyor (121, 122) configured to stack and transport the plurality of connected cardboard box bodies; a loading lower conveyor disposed upstream of the lower conveyor (121, 122) in a transport direction (Da) of the connected cardboard box bodies and a loading upper conveyor disposed so as to face the loading lower conveyor from above; a pressing device configured to press, from above, the plurality of connected cardboard box bodies stacked on the lower conveyor (121, 122); a cutting blade disposed along a width direction (Db) of the connected cardboard box body, configured to divide the plurality of connected cardboard box bodies stacked on the lower conveyor (121, 122) into a front part and a rear part; a lifting/lowering device configured to move relatively the plurality of connected cardboard box bodies on the lower conveyor (121, 122) and the cutting blade along an up-down direction; and a control device configured to control the pressing device, wherein a reference pressing reaction force is a pressure at which the pressing device presses and holds the plurality of stacked connected cardboard box bodies, characterised in that the box dividing device further comprises a height detector configured to detect a lifting/lowering height of a pressing measurement member at a time when a pressing reaction force acting on the pressing measurement member from the plurality of stacked connected cardboard box bodies reaches the reference pressing reaction force, wherein the control device is configured to control the pressing device based on a detection result of the height detector, the pressing device having a pressing member (149 to 152) configured to be supported so as to be capable of ascending and descending and a pressing drive device configured for lifting and lowering the pressing member (149 to 152), the control device being configured to control the pressing device based on a lifting/lowering height of the pressing measurement member at a time when the pressing reaction force from the connected cardboard box body, at a time when the pressing measurement member presses the plurality of stacked connected cardboard box bodies, reaches the reference pressing reaction force, and to adjust a pressing position of the pressing member (149 to 153) by the pressing drive device, and wherein the pressing measurement member is the loading upper conveyor. a lower conveyor (121, 122) configured to stack and transport the plurality of connected cardboard box bodies; a loading lower conveyor disposed upstream of the lower conveyor (121, 122) in a transport direction (Da) of the connected cardboard box bodies and a loading upper conveyor disposed so as to face the loading lower conveyor from above; a pressing device configured to press, from above, the plurality of connected cardboard box bodies stacked on the lower conveyor (121, 122); a cutting blade disposed along a width direction (Db) of the connected cardboard box body, configured to divide the plurality of connected cardboard box bodies stacked on the lower conveyor (121, 122) into a front part and a rear part; a lifting/lowering device configured to move relatively the plurality of connected cardboard box bodies on the lower conveyor (121, 122) and the cutting blade along an up-down direction; and a control device configured to control the pressing device, wherein a reference pressing reaction force is a pressure at which the pressing device presses and holds the plurality of stacked connected cardboard box bodies, characterised in that the box dividing device further comprises a height detector configured to detect a lifting/lowering height of a pressing measurement member at a time when a pressing reaction force acting on the pressing measurement member from the plurality of stacked connected cardboard box bodies reaches the reference pressing reaction force, wherein the control device is configured to control the pressing device based on a detection result of the height detector, the pressing device having a pressing member (149 to 152) configured to be supported so as to be capable of ascending and descending and a pressing drive device configured for lifting and lowering the pressing member (149 to 152), the control device being configured to control the pressing device based on a lifting/lowering height of the pressing measurement member at a time when the pressing reaction force from the connected cardboard box body, at a time when the pressing measurement member presses the plurality of stacked connected cardboard box bodies, reaches the reference pressing reaction force, and to adjust a pressing position of the pressing member (149 to 153) by the pressing drive device, and wherein the pressing measurement member is the loading upper conveyor.