PURPOSE: To obtain a cermet tool improved in toughness to a greater extent by binding a hard dispersed phase consisting of the carbonitrides of Ti, W, and one or more elements selected from Mo, Nb, and Ta with a binding phase containing Ni and Co, applying grinding work to the above, and then subjecting the above to annealing under specific conditions.

CONSTITUTION: A hard dispersed phase consisting of the carbonitrides of Ti, W, and at least one transition metal selected from Mo, Nb, and Ta is bound with a metallic binding phase containing Ni and Co, by which a cermet is prepared. This cermet is subjected to grinding work so as to be finished into a tool shape, annealed at 700-1,300°C in vacuum, etc., for 15min-2h. By this method, toughness can be improved to a greater extent, and the tough cermet tool sufficiently usable as drills, end mills, etc., in which breakage becomes a critical defect can be obtained.