A polishing apparatus is a cluster type of apparatus having a plurality of units to deal with various works. The polishing apparatus includes a universal transfer robot having at least one arm for transferring a workpiece, a plurality of units disposed around the universal transfer robot and including a loading unit for placing thereon the workpiece to be polished, at least one polishing unit for polishing the workpiece, at least one washing unit for washing the workpiece which has been polished and an unloading unit for placing thereon the cleaned workpiece. The polishing apparatus further includes an exclusive transferring device for transferring the workpiece between two units of the plurality of units adjacent to each other. The universal transfer robot transfers a clean workpiece and the exclusive transferring device transfers a dirty workpiece. The loading unit and the unloading unit are integrally formed.