The utility model relates to a mill's burnisher, more specifically the mill uses self - cleaning device that says so, the device can clean ground automatically to through adjusting, the cleaning head is parallel with ground all the time, conveniently cleans, the device has the wheel, is convenient for remove, when the device does not use, accepts the wheel for what the device was placed is stable good. The lower extreme and the belt cleaning device bulk phase of connecting rod are connected, the upper end and the straight -bar swing joint of connecting rod, the one end and the connecting rod swing joint of pneumatic cylinder I, the other end and the straight -bar swing joint of pneumatic cylinder I, straight -bar and device main part swing joint, the one end and the straight -bar swing joint of pneumatic cylinder II, the other end and the device main part swing joint of pneumatic cylinder II. The lower extreme at the base is installed at the lower extreme of device main part, recess to the pedestal mounting, and pneumatic cylinder III, connecting piece, universal wheel support and universal wheel all set up the inside at the recess.