PURPOSE: To obtain a steel strip having excellent cold workability and mechanical strength such as resistance to fatigue and elongation by controlling the working heat generated in the stage of cold rolling the patenting steel strip to a specific temp. or below.

CONSTITUTION: The working heat to be generated in the stage of cold rolling of the patenting steel strip consisting of a carbon steel or low alloy steel is controlled to ≤200°C, more preferably ≤150°C in the stage of said rolling. The control of the working heat is executed by adjusting rolling conditions including reduction rate of area, speed, etc. or adjusting the injection rate of a rolling mill oil, etc. The steel strip obtd. by the above-mentioned method has excellent cold workability such as cold rolling, bending, blanking, etc. and excellent mechanical properties and is therefore suitable as a blank material for parts such as a coil spring and leaf spring.