An X-ray spectrometer is provided with: an excitation source configured to irradiate excitation rays onto an irradiation area of a sample, a diffraction member provided to face the irradiation area; a slit member provided between the irradiation area and the diffraction member, the slit member having a slit extending parallel to the irradiation area and a prescribed surface of the diffraction member; an X-ray linear sensor having a light-incident surface in which a plurality of detection elements are arranged in a direction perpendicular to a longitudinal direction of the slit; a first moving mechanism configured to change an angle between the sample surface and the prescribed surface, and/or a distance between the sample surface and the prescribed surface by moving the diffraction member within a plane perpendicular to the longitudinal direction; and a second moving mechanism configured to position the X-ray linear sensor on a path of characteristic X-rays passed through the slit and diffracted by the prescribed surface by moving the X-ray linear sensor within a plane perpendicular to the longitudinal direction.