PURPOSE: To prevent the occurrence of flaws by the dust in a later process by eliminating the dust to stick on the surface of a substrate during press work.

CONSTITUTION: This substrate pressing device is provided with a pair of die 1 and punch 6, by which a substrate fragment formed into the outer shape of a die hole 2 shape is obtained from a glass epoxy plate 8, a punch holder 5 for supporting the punch 6 freely insertably into the die hole 2 of the die 1, and a stopper 9 which is arranged between the punch holder 5 and the die 1 and fixes the glass epoxy plate 8, while air holes 7, 12, through which air blowing or air suction is performed against the surface of the substrate fragment, are formed in the punch 6 or the stopper 9.