PURPOSE: To produce an as-hot-rolled high strength steel plate excellent in ductility and strength by hot-rolling a slab of a low- or medium-carbon steel with a specific composition under specific conditions and then cooling the resulting plate in three stages.

CONSTITUTION: A slab of a steel which has a composition containing, by weight, 0.08-0.40% C, 0.8-2.5% Si, 0.8-4.0%, in total, of Mn and/or Cr, 0.001-0.050% sol.Al, and 0.0080-0.0250% N, or further containing 0.003-0.030% Ti or 0.003-0.030% Nb or 0.5-3.0% Cu and/or <1.5% Ni, or further containing at least one kind among 0.0002-0.01% Ca, 0.01-0.10% Zr, and 0.002-0.10% rare earth elements is reheated at a temp. not lower than the Ac3 point so that average austenite grain size is regulated to ≤50μm, and, after hot rolling is finished at a finishing temp. between Ar3 and (Ar3+50°C), the resulting plate is cooled down to 550-700°C at ≤60°C/sec cooling rate and further subjected to coolings in a second and a third stage, respectively, under dissimilar colling conditions, followed by coiling. By this method, the hot rolled steel plate for working which has a dual-phase structure consisting of polygonal ferrite and retained austenite and has superior workability and ductility can be produced.