An X-ray apparatus includes: a collimator for adjusting an X-ray irradiation region; a data obtainer for obtaining position information of a target in an object based on an electrode signal sensed from electrodes attached to the object; and a controller for setting first coordinates indicating a position of the target on a first coordinate system with respect to the object based on the position information, transforming the first coordinates to second coordinates on a second coordinate system with respect to an X-ray image of the object, and adjusting a position of the collimator based on the second coordinates.