A box packing system includes a frame, a cardboard sheet feeder, a box making section and a box packing device. The cardboard sheet feeder is configured to lift one of a plurality of cardboard sheets from a cardboard sheet stacking area of the frame. The cardboard sheets are in an upright state within the cardboard sheet stacking area and are folded or collapsed. The box making section re-shapes the cardboard sheet unfolding the cardboard sheet and transforms the cardboard sheet into a cardboard box where a bottom lid is closed and a top lid is opened defining an opening of the cardboard box. The box packing device has a dropping part that moves the cardboard box in a laterally opened state downwardly to s located filling position and a pushing part that pushes an article into the opening of the cardboard box while within the filling position.