PURPOSE: To stabilize the quality of a heated slab and to reduce the unit con sumption of fuel by properly deciding a charging interval and an ejecting inter val of steel slabs on the capacity of a heating furnace and the capacity of a rolling line, at the time of heating the steel slabs to the rolling temp. in the continuous type heating furnace for hot-rolling.

CONSTITUTION: At the time of charging plural steel slabs into the continuous heating furnace in order and heating the steel slabs up to the hot-rolling temp. while shifting them in the furnace, in the case the heating furnace restriction ejecting interval of an object slab obtd. from a target furnace staying time of the object slab is larger than the rolling restriction ejecting interval of the object slab obtd. from the ability of a succeeding hot rolling line, the object slab is charged into the furnace succeedingly to the slab charged just before without stopping and the heated slab is ejected at the heating furnace restriction ejecting interval. On the contrary, the object slab is charged succeedingly to the slab charged just before at an interval of time decided from the difference between the rolling restriction ejecting interval and the heating furnace restriction ejecting interval and ejected from the heating furnace at the rolling restriction ejecting interval.