PURPOSE: To work a groove finely and correctly, by forming a groove on the surface of a metal material of good lathe turning property with the use of a cutting tool, making a die impressed with this groove and forming the groove on a resin material being hot-pressed by using this die.

CONSTITUTION: Grooves 6, 7 becoming the origin of the groove of a polishing plate are worked on the surface of a metal material 10, by moving a cutting tool 11 in the direction orthogonal with a rotating axial line while rotating a metal material 10 of good lathe turning property. Then dies 20, 25 impressed with this groove 6 and 7 are made. The polishing plate 3 formed with the grooves 6, 7 is manufactured by heating the resin material 30 while pressing the dies 20, 25 to the resin material 30. The grooves 6, 7 can be worked finely and correctly, because of the grooving by the cutting tool 11 being executed on the metal material 10 of good lathe turning property like this, and fine and accurate grooves 6, 7 can be formed on a resin plate 30, with the grooves 6, 7 being correctly transferred on the resin made plate 30 by using the dies 20, 25.