PURPOSE: To prevent top marks by biting the tip and rear end of a a strip between rolling rolls.

CONSTITUTION: This device consists of tip and rear end detector 4 for the strip 3 which is arranged on the inlet side of a rolling mill 1, induction heating device 6 which is arranged in the breadthwise direction of the strip between the tip and rear end detector 4 for the strip 3 and the rolling mill 1 and heating control part 7 with which a prescribed length at the tip or the rear end of the strip 3 is annealed by impressing a high frequency power source in the induction heating device 6 based on the detection signals of the tip and rear end of the strip 3 that are inputted from the tip and rear end detector 4 for the strip 3 and passing speed. In this way, roll marks which are generated at the time of biting into the rolling mill or end passing-through of a material to be rolled by softening burrs and work-hardening part which are generated by shear cutting at a pre-stage are prevented and the roll marks of the material to be rolled can be completely eliminated.