To provide a grinding method of a drill capable of easily and accurately executing work for forming first and second beveling surfaces which are made from plane surfaces and wide at outer ends so as to be symmetrical about an axis.

In the grinding method of the twist drill, a ruler material 34 moving forward/backward on a tilting straight line A3 having a downward tilting angle is provided at a front side of a drill 28 held in a drill holder. A horizontal ruler surface 37 shifted in parallel by backward/forward movement of the ruler material 34 is provided at a tip end of the ruler material 34. The ruler material 34 is moved forward to set a parallel shift level of the horizontal ruler surface 37. Cutting edge rake faces 5, 6, are corner-contacted on the horizontal ruler surface 37. By corner contacting, cutting edges 1, 2 tilt downward to a generating line A5 of a tilting grinding surface 31 of a rotating disc-shaped grinding wheel 24. In the tilting state, the drill holder and the drill 28 are moved forward, thereby grinding beveling surfaces 9, 10 which are wide W at the outer ends on cutting edge flanks 3, 4.