To provide a stamping process machine which is capable of stabilizing a stamping condition regardless of a bundle condition and increasing a processing efficiency and further, mitigating an operating burden of an operator.

This stamping process machine 100 comprises a conveyor 51 which conveys sheets disposed at the lower end of a bundle T in the stacking direction, in such a manner that a conveying face 101a is brought into contact face to face with the sheets, a height detection part 110 which detects the height of the bundle T, in the stacking direction, to be deposited on the conveying face 101a and conveyed, a stamping device 50 which presses a stamper 113 whose stamping stroke is adjusted in accordance with the height detected by the height detection part 110, on a belt wound around the upper end of the bundle T and an inspection part 52 which inspects a printing state created by the stamping device 50. As a result of the inspection, the inspection results are fed back to the following bundle in its process so that the stamping time and stamping interval by the stamper 113 can be adjusted, when the print density is low.