PURPOSE: To avoid generation of burrs, by a method wherein a groove is formed by a rotary blade prior to a sawing work of a round bar and cutting is carried out by the blade of a sawing machine under a stationary state of the round bar.

CONSTITUTION: A round bar 2 is clamped by a pair of roller supporting frames 9 and 10. Prior to sawing of the round bar 2, driving rollers 12 and 12a of the frames 9 and 10 are revolved and a groove 7 is formed by making use of the blade 4 under a revolving state of the round bar 2. Then, conventional sawing work is performed by the blade 4 under a suspended state of the movement of the round bar. Uncut part 5 separated on one side of the inside of the groove 7 becomes the wall of the side of the groove 7, which is cut off by the blade 4 completely and burrs are not generated.