PURPOSE: To execute rolling with low thickness deviation rate by moving in the rolling direction the vibration restraining means holding the outer periphery of the mandrel bar of the vicinity of the tip part and the outer periphery of the tip part of a rolling blank pipe simultaneously with the moving speed of the rolling blank pipe.

CONSTITUTION: At the time when the distance between the tip of the rolling blank pipe P coming out of the outlet side of a rolling roll 11 and the rear end of a mandrel bar vibration restraining means 16 becomes of the specified value, a distance detection signal is outputted from a laser distance meter 20. A blank pipe vibration restraining means 15 is subjected to a closing operation via the control device actuated thereby and a reversible moving means 19 is driven as well. Namely the rolling speed of the rolling blank pipe P is detected and the rotary speed of a screw shaft 19b in the reversible moving means 19 is controlled via a control device based on this rolling speed detection value. The vibration of the pipe blank and mandrel bar can thus be reduced by holding the outer periphery of the mandrel bar of the tip vicinity and the tip part outer periphery of the blank pipe from the beginning up to the last in rolling and the rolling can be executed with a low thickness deviation rate.