PURPOSE: To obtain an excellent screwed-knotted type high strength bar by a method wherein R on a joint of a knot contacting with the exterior of the screwed-knotted bar, R on a joint of a rib of the screwed-knotted bar, and R on a corner where the knot and the rib intersect are made, against the nominal diameter (d) of the screwed-knotted bar, to become an R/d value within a specified range.

CONSTITUTION: For knots and ribs, deformed shapes on the exterior of a screwed-knotted bar, R on a joint of a knot contacting with the exterior of the screwed-knotted bar, R on a joint of a rib of the screwed-knotted bar, and R on a corner where the knot and the rib intersect are made, against the nominal diameter (d) of the screwed-knotted bar, to become R/d=0.125-0.30. Therefore, bending performance for a high strength bar in 490-685N/mm2 of yield point strength can be improved, and a reinforcing bar that is available for bending processing where bending at an angle of 90° can be made with the inside bending radius being 1.5 times the nominal diameter, or excellent in bending processing resistive against return bending at an angle of 30° after the bending processing can be obtained.