PURPOSE: To offer the precision punching die assembly which can manufacture a product in which a precise punched hole is formed without spoiling the beauty of a bridge part in which a sheet-like stock remains and its torn surface, and also, to prevent the damage of a punching die.

CONSTITUTION: This assembly constitutes a characteristic feature of attaching integrally a stripper 3 to a ram 22 of a press machine through a punch die set 13, placing a punch plate unit 12 so as to be movable vertically in the stripper 3, protruding the tip part of a punch 5 provided on the punch plate unit 12 to the lower part through a punch guide hole 71 provided on the stripper 3, and also, providing a punch plate unit driving means 14 for moving the punch plate unit 12 independently from the ram 22.