Abstract: The paper gives an overall view of the research results gained by some manufacturers such as Lenin Steel Tube Works in the past over ten years,involving the materials,manufacturing processes and service-life increasing measures with respect to the piercing mandrel plug,and particularly coveringd etails about the precision hot die forging technique for the mandrel plug.Considering the fact that China lags far behind the Soviet Union in manufacture,application and development of piercing mandrel plug,the experience introduced by the paper is therefore very valuable for helping us speedup the progress in the above mentioned field.