Provided is an object shape detection apparatus that can detect the shape of a raised or depressed portion on the surface of an object. In accordance with a comparison result obtained by a reflection intensity comparator with regard to intensity of a horizontally polarized wave component and a vertically polarized wave component of a reflected wave, the object shape determiner detects the shape of the raised portion and the shape of the depressed portion of a detection target object. The object locator detects the position of the raised portion and the position of the depressed portion of the detection target object by measuring the distance to the raised portion and the distance to the depressed portion of the detection target object detected by the object shape determiner.