PURPOSE: To permit the certain and simplified polishing by using the polishing material which is insoluble into water and can be made plastic by heating and easily shaped to a desired form and solidifies through cooling.

CONSTITUTION: The abrasive material applied onto an abrasive plate 1 is constituted of combining at least one kind of inorganic superfine particles such as cerium oxide, etc. commonly used and mixing plastic bonder. The plastic binder is insoluble into water and possesses adhesive force, and formed by solidifying and shaping the inorganic superfine abrasive grains into pellet form, and can be made plastic by heating a little and can be shaped to a desired form, and a workpiece can be made free from the outside appearance trouble of flaws and sand trace, etc. When the polishing material is made plastic by heating and extended by the pushing by a surface plate 2, said material is attached onto the polishing plate 1, and a desired curved surface is formed, and said curved surface is fixed through cooling. Through frictional heat is generated in polishing, cooling is performed, and plasticization does not occur, since the water for polishing in which abrasive grains are mixed is allowed to flow. Therefore, a prescribed surface precision is generated in a short time.