PURPOSE: A grinding device is provided to reduce the power consumption because it can be driven with the less power in comparison with a case in which a grinding unit is rotated at high speed and to minimize entire sizes of the grinding device by forming a motor to be rotated with the grinding unit. CONSTITUTION: A grinding device includes a grinding unit. The grinding unit grinds a rod of a breaker mounted on construction equipment. The grinding unit rotates to the rod as a rotary shaft. The grinding unit includes cutters (141, 142) arranged to be inclined in a longitudinal direction of the rod. The inclined angle of the end of the rod is determined to the inclined angle of the cutter.
