The invention discloses a workpiece polishing device which comprises a rectangular base. Strip-shaped grooves are machined in the two sides of the upper surface of the interior of the rectangular base, a miniature rotating motor with the upward rotating end is embedded into each strip-shaped groove, an electric control stretchable rod is fixedly connected to the rotating end of each miniature rotating motor, a rotating rod is installed on each miniature rotating motor in a sleeving manner, a zigzag form swing rod is fixedly connected to each rotating rod, a rotating round shaft is fixedly connected to each zigzag form swing rod, a rotating wheel is installed on each rotating round shaft in a sleeving manner, and a polishing roller is fixedly connected to each rotating wheel jointly. The workpiece polishing device has the beneficial effects that the structure is simple, the swing angle is good, polishing is convenient, the labor intensity is reduced, and the efficiency is improved.