PURPOSE: To produce a thin sheet of rimmed steel which hardens during baking of painting by subjecting rimmed steel contg. C, Mn, P, S, N, etc. in a limited compsn. range to hot and cold rolling then to annealing which controls the contents of C and N.

CONSTITUTION: The rimmed steel consisting of ≤0.09% C, 0.15W0.45% Mn, ≤ 0.03% P, ≤0.03% S, ≤0.006% N, and the balance Fe and unavoidable impurities is subjected to ordinary hot rolling then to coiling at ≤600°C followed by pickling and cold rolling at ≥40% draft. Thereafter, the cold rolled steel plate is annealed by heating the same in a 580W740°C temp. region in a gaseous atmosphere contg. H2 and N2 for ≥3hr and holding the plate at said temps. to control C to ≤0.004% and N to 5W15ppm. Such steel plate is subjected to skin pass rolling of about ≤1% by an ordinary method, whereby the thin sheet of rimmed steel having good deep drawability and shape characteristic, about ≥ 3kg/mm2 rate of thermal hardening and small yield elongation is obtained.