The invention relates to a leather polishing device, in particular to a leather polishing device for a cosmetic bag. The technical purpose is to provide the leather polishing device for the cosmetic bag. To achieve the technical purpose, the leather polishing device for the cosmetic bag comprises a top plate, fulcrum bars, first compression rollers, second compression rollers, expansion links, rotating equipment, a grinding disk, electromagnets, hammering rods, guide rails, check blocks and the like. Belt conveying devices are arranged on the top and the middle portion of a bottom plate. The parts, on the left side and the right side of the belt conveying device, of the bottom plate are symmetrically provided with the expansion links. The upper ends of the expansion links are rotationallyconnected with the second compression rollers. The second compression rollers are flush to the top of the belt conveying device. The inner side walls of the belt conveying device are provided with theguide rails. By means of the leather polishing device for the cosmetic bag, the effects that the leather polishing efficiency is high, the smoothness of the belt polishing conveying process can be guaranteed, and fragments are treated in time after leather is polished and are prevented from affecting the leather polishing efficiency and the polishing effect are achieved.