PURPOSE: To extend the service life of a tip that uses as a cutting edge a high- hardness sintered compact containing a diamond or a cubic system boron nitride, by preventing the occurrence of breakage or crack at a boundary portion between the base material and sintered compact tip portion.

CONSTITUTION: In a cutting tool comprising a high-hardness sintered compact 2 containing a diamond or a cubic system boron nitride, the sintered compact 2 being bonded to a corner portion 11 of a base material 1 consisting of hard material, the end portion of the sintered compact 2 positioned at a vertical wall side of the base material 1 is chipped off to provide a tip.