PURPOSE: To dispense with the manual measurement of dimensions of cutting tools so as to enable the regrinding of the tools in a short time and to make efficient use of the tools, in the regrinding of the cutting tools.

CONSTITUTION: The relative position between a cutting tool and a measuring instrument is controlled with a control means to measure dimensions of the tool before regrinding (S2). Then the relative position between the cutting tool and a grinder is controlled to regrind the tool from a regrinding base point based on the measured tool dimension data (S3, S4). Then the relative position between the cutting tool and the measuring instrument is controlled to measure the tool dimensions (S5), and the tool dimension data measured after regrinding are stored in a memory means (S6) to use as the tool dimension data in a work process.