To provide a printed board processing machine which processes a hole with a high accuracy and which provides a processing at a lower cost.

A sub-plate 15 supported so as to be movable along the Y axis is provided between a clamp plate 8 and a side face 5b provided behind a hole 5. When the clamp plate 8 locates a reference pin 3 fixed on a printed board 2, then the sub-plate 15 is located at the intermediate point between the clamp plate 8 and a side face 5b provided at the right inner side of the hole 5.