A hot rolling line is constructed by a pair or a plurality of pairs of rolling rolls disposed opposingly on an upper side and on a lower side of a workpiece (1) to be rolled that is pinched in between the rollers. A descaling apparatus (5) has jet flow nozzles disposed so that two jetted flows, being liquid, gas or plasma, are opposing flows so as to collide with the surface of a strip on the upstream side of the rolling rolls and then collide with each other. The jet flow nozzles are disposed, so as to incline in a direction to face each other so that the angle of inclination is 15 DEG to 60 DEG from the horizontal direction of the strip surface.
