Reinforcing steel bar threading size marker

The invention discloses a reinforcing steel bar threading size marker, which comprises a marking rod, a positioning stop rod and a nozzle. The marking rod comprises a vertical section and a horizontalsection; the vertical section is perpendicularly connected with the horizontal section; the horizontal section is parallel to a reinforcing steel bar to be marked; the positioning stop rod can be slidably arranged on the horizontal section, is parallel to the vertical section, and is used for pressing against the end part of the reinforcing steel bar to be marked; and the nozzle is fixed on the end part, far away from the horizontal section, of the vertical section, communicates with an oil paint storage tank, and is used for spraying an oil paint on a position, which is designed-size far away from the end part of the reinforcing steel bar to be marked, on the reinforcing steel bar to be marked. The reinforcing steel bar threading size marker provided by the invention can be used for quickly finding out a marking