This application relates to an absolute position detection device and detection method of a rotating body using a magnetic material. The device may include magnets coupled to a rotating body and configured to rotate together and having n pole pairs, wherein n is a natural number and (n+1) magnetic materials arranged adjacent to the magnets, spaced apart from each other by a predetermined interval, and configured to rotate together with the rotating body. The device may also include a first Hall sensor spaced apart from the magnets, installed to allow the magnetic materials to rotate in a space between the first Hall sensor and the magnets and configured to output a first signal based on the magnets when the magnetic materials approach the first Hall sensor. The device may further include a controller configured to measure an absolute position of the rotating body using the first signal.