To provide a magnetic encoder which can be assembled having a thin-walled structure while securing an excellent detection sensitivity and which can provide an excellent moldability by suitably selecting materials, the magnetic encoder is provided which includes a multi-pole magnet 14 having a plurality of opposite magnetic poles alternating in a direction circumferentially thereof, and a core metal 11 for supporting the multi-pole magnet. The multi-pole magnet 14 contains a powdery magnetic material mixed in an amount within the range of 20 to 90 vol. % relative to the total volume of the multi-pole magnet 14. The multi-pole magnet 14 may be a sintered magnet.