A magnetic encoder structure according to an exemplary embodiment of the present invention includes: a back plate; and a magnet rubber which has a ring shape, and is vulcanized and attached to a rear surface of the back plate, in which the magnet rubber has a plurality of protruding portions which protrudes from an adhesive surface that is attached to the back plate, and groove portions which are formed between the protruding portions, and the protruding portions and the groove portions are repetitively disposed in a rotation direction of the magnet rubber.