PURPOSE: To perform the detaching motion of a polishing plate quickly and surely, by composing it so as to detach the polishing plate with a negative pressure or positive pressure being fed alternately to the vent hole of an attraction base by a pressure source.

CONSTITUTION: A polishing plate 4 is made by bonding a polishing sheet 2 to the adhesive face of a polishing seat 3 mated with the polishing face of the body 1 to be polished. The polishing plate 4 is then attracted to an attraction base 5 with a negative pressure being fed to this attraction base 5 by a pressure source 25. Thereafter, the air motor inside the tool main body 18 is driven and the body 1 to be polished is subjected to polishing with the polishing sheet 2 of the polishing plate 4 attracted to the attraction base 5 being slid while bringing it into contact with the body 1 to be polished above. Then, a positive pressure is fed onto the attraction base 5 and the polishing plate 4 completed with the polishing termination is separated from the attraction base 5.