In cutting tool assembly, grinding is the most important technological step of the finishing treatment, largely determining the workmanship. An increase of micro-hardness after grinding relative to the original one indicates the dominant role of abrasive tool force impact on the ground surface. A decrease, in contrast, evidences a significant softening under the influence of heat source. This research based on nonparametric statistics to predict the effect of wheel characteristics with abrasives 25A, 92A/25A, 34A, 5A, EKE, 5NQ, TGX, 5SG and with graininess 46 (F46), 60 (F60), 80 with different porosities (structure numbers 6-12), and the expected measures of position and dispersion on the micro-hardness of the surface of a high-speed cutting plate (HSCP) made of W9Mo4Co8 steel. It was found that grinding this HSCP by wheels 5NQ46I6VS3,