PURPOSE: To shorten the time required to remove scale on the surface of a hot rolled steel plate by pickling by cold-rolling the plate at a specified reduction ratio and carrying out liq. honing before descaling.

CONSTITUTION: Hot rolled steel plate 1 with scale stuck to the surfaces is cold rolled at 10W40% reduction ratio with cold rolling mill 2 to crush and crack the scale. Plate 1 is then passed through liq. honing device 3, where a granular abrasive material is sprayed together with water or the like to remove part of the scale mechanically. The residual scale is removed by dissolution in acid in pickling vessel 4. The resulting steel plate thoroughly free from scale is washed in washing vessel 5 to remove the acid, and it is dried with dryer 6.