PURPOSE: To manufacture a seamless pipe made of a high alloyed steel, etc., with high rolling efficiency.

CONSTITUTION: A billet made of an alloyed steel containing Cr or Ni with at least 5wt.% or over or an alloy whose main components are Cr, Ni or Mo, is pierced by using a piercing plug made of Mo, Mo alloy or a heat resisting steel. A plate is joined on an end face on a side on which the piercing of the billet is started, or plates are jointed on both end faces. The billet with a plate (or plates) joined in this way is hot-pierced by using a piercing plug to process a hollow base stock. By rolling the attained hollow base stock, a seamless pipe is manufactured. Consequently, the resistance of the plug is improved, the life of the plug is extended, the frequency of a plug replacement is reduced, and the reduction in the consumption unit of a tool is attained.