To provide an accurate feeding device which is free from vibration as disturbance, is excellent in positioning accuracy, and allows a vibration attenuation effect to be hardly affected by the change in mass of a mounted object.

This device is provided with an air sliding device 15, an actuator 16, and with a displacement sensor 17, and the device can be applied to an accurate feeding device capable of positioning a moving part 4 by means of a feed-back control. The air sliding device allows the moving part 4 to be supported by a guide 3 in such a way as to be freely advanced/retreated by way of a direct acting type static pressure air bearing. The displacement sensor 17 is formed out of a detected part 7 to be provided for the side surface of the moving part 4, and of a detection part 9 whose position is fixed. In this constitution, the detected part 7 of the displacement sensor 17 is disposed at the center O in the height direction over the side surface of the moving part 4.