PURPOSE: To improve economic efficiency and cutting precision by arranging the notched parts at equal intervals onto a cutting-edge formation part formed into tooth form and forming the cut parts onto an annular disc corresponding to the notched parts.

CONSTITUTION: A cutting-edge formation part 2 is formed thinner than the thickness of an annular disc 1, and formed into comb shape, and a cutting-edge part 7 is formed by attaching minute diamond grains 6 onto the surface. The connection part 5 with the root parts 4 and 4 of the cutting-edge formation part 2 is formed into circular form. In the round saw thus formed, the notched parts 10 having a proper width are arranged at equal intervals onto the cutting- edge formation part 2 formed into tooth form, and the cut parts 11 are formed by a circular curve onto the annular disc 1 corresponding to the notched parts 11. Therefore, the efficiency of cooling effect can be improved by improving the flow of water or cutting oil.