Abstract: A rotation detecting apparatus including a magnet having alternatively-arranged N-poles and S-poles on a rotator, and a magnetoresistive element having plural (six) magnetoresistive units which are continuously arranged at a predetermined interval on a stator, and signal output units which are provided at prescribed three positions of connection points of the plural detection units, wherein the detection units serving to detect magnetic field which is varied in accordance with rotation of the rotor, and the signal output units serving to output signals whose phases are different from one another by 120.degree. on the basis of the detection of the magnetic field by the detection units.