PURPOSE: To widen a range for production by rolling and a range for temp. control by providing a coil box to the inlet side of a finishing mill train of a continuous hot rolling line and providing a high-draft rolling mill to the inlet side of the coil box between said mill train and a roughing mill train.

CONSTITUTION: A slab S heated in a heating furnace 5 is rolled in a suitable number of passes by a scale breaker 12 and roughing mill group 13 of the roughing mill train 1. The roughened bar S1 is conveyed on a delay table 6 up to a high-draft rolling mill 2. The rolling mill 2 rolls down the roughened bar S1 down to the thickness to permit coiling while controlling the inlet side temp. to the coil box 4 and the coiling temp. and the rolled bar is coiled in the coil box 4. The rolled stock un-coiled from the box 4 is rolled down to the final thickness in the finishing mill train 3 and is coiled as a product on a down coiler 7. The range for the production by rolling and range for the temp. control of the rolling mill train are thereby widened at a min. equipment cost.