PURPOSE: To enable a plural number of boxes housing particles to be automatically lined up in order so as to be stacked, and thereby facilitate case packing into a carton to save much labor as well as to enhance efficiency.

CONSTITUTION: The device is provided with a device frame 11 set at one side of a box carrying conveyor 3, a box stacking table 12 provided in frame 11 in such a way as to be moved up and down, a movable framework 13 which is provided for the upper end of the frame 11 so as to be reciprocally moved in parallel with the conveyor while let the frame itself come in and out over the table 12, and with a box line-up table 14 provided at the lower section within the framework 13. Furthermore, the device is equipped with a box lateral feed stacking means 16 disposed in the movable framework 13 in such a way as to be capable of being reciprocally moved in the direction identical to the moving direction of the framework 13 above the box line-up table 14, a box draw means 15 drawing boxes over the conveyor 3 into the line-up table 14 so as to be lined up in a longitudinal row, and with a stacking push-out means 17 pushing out stacked boxes over the table 12 so as to be pushed in a housing container 18.