According to the present disclosure, there may be provided a pressure pad sensor pressing device including a pressing unit including a node pressing portion provided to descend from a predetermined height and contact one of the sensing nodes, and a weight loading portion provided at the top of the node pressing portion so that a weight load is transmitted to the node pressing portion; a support frame supporting the pressing unit at a predetermined height; and a first driving unit for moving the pressing unit in the first direction or in the reverse direction, a second driving unit for moving the pressing unit in the second direction or in the reverse direction, and a third driving unit for lifting and lowering the pressing unit with respect to the pressure pad sensor, and a calibration method capable of calibrating the output value of the sensing node to a reliable pressure value using the pressure pad sensor pressing device.