In grinding of a raw material by a vertical roller mill, highly-efficient grinding is performed irrespective of the type of the raw material, and the life of the mill roller is extended. In order to achieve these, in a grinding roller used in a vertical roller mill, an outer circumferential surface of the roller as a grinding surface is divided into a main grinding surface that mainly performs pulverizing and a grinding surface other than the main grinding surface. The main grinding surface is made smooth, and the grinding surface other than the main grinding surface is a raw material transfer surface in which slit grooves inclined at 90 degrees or an angle exceeding 45 degrees relative to a roller circumferential direction or screw grooves inclined at 45 degrees or smaller relative to the roller circumferential direction are formed.
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