An inspection apparatus for inspecting an inspection target object, includes an X-ray generation tube having a target including an X-ray generation portion that generates X-rays by irradiation with an electron beam, and configured to emit X-rays to the inspection target object, and a plurality of X-ray detectors, wherein each of the plurality of X-ray detectors detects X-rays emitted from a foreign substance existing on an inspection target surface of the inspection target object irradiated with the X-rays from the X-ray generation portion and totally reflected by the inspection target surface.