BOX PACKING DEVICE

It is an object of the present invention to provide a reliable box packing device that inhibits the occurrence of a problem where, when packing an article into boxes, the article end up rotating in the boxes. A box packing device (10) includes a push-in mechanism (50), a retention mechanism (30), a guide (70), and a control unit (100). The push-in mechanism (50) pushes, into a cardboard box (C) that is in a state in which an opening (Op) thereof faces sideways, the article (A) through the opening (Op). The retention mechanism (30) retains the cardboard box (C) that is in a state in which the opening (Op) faces sideways and lowers the cardboard box (C) after the article (A) have been pushed into the cardboard box (C) by the push-in mechanism (50). The guide (70) opposes the opening (Op) and is a member for preventing the article (A) from falling out from the opening (Op) of the cardboard box (C) that has been lowered by the retention mechanism (30). The control unit (100) temporarily increases the distance between the cardboard box (C) and the guide (70) after the article (A) have been pushed into the cardboard box (C) by the push-in mechanism (50).