A magnetic wave gear device in which a stator, a first rotor, and a second rotor are provided in a concentric shape, a center of which is a rotational axis, wherein: the first rotor is radially disposed between the stator and the second rotor, and has first magnetic bodies and first permanent magnets, in which the first magnetic bodies are arranged around the rotational axis at regular intervals, and the first permanent magnets are each arranged between the neighboring first magnetic bodies in a circumferential direction, and the first permanent magnets are all magnetized outward, and magnetic poles thereof are made identical; the second rotor has second magnetic bodies and second permanent magnets, in which the second magnetic bodies are arranged around the rotational axis at regular intervals, and the second permanent magnets are each arranged between the neighboring second magnetic bodies in the circumferential direction, and like directions of the magnetic poles of the first permanent magnets, the second permanent magnets are all magnetized outward, and magnetic poles thereof are made identical; the stator has third magnetic bodies that protrude inward in a radial direction and which are provided with slots in which coils can be wound, the coils being wound around the third magnetic bodies, and third permanent magnets, in which the third magnetic bodies are arranged around the rotational axis at regular intervals and the third permanent magnets are each arranged between the neighbouring third magnetic bodies in the circumferential direction, and like directions of the magnetic poles of the first permanent magnets, the third permanent magnets are all magnetized outward, and magnetic poles thereof are made identical; and a relationship of Ns = Nl±Nh is satisfied when Nl is the number of magnetic poles of the first rotor, Nh is the number of pole pairs of the second rotor, and Ns is the number of slots of the stator. the first rotor is radially disposed between the stator and the second rotor, and has first magnetic bodies and first permanent magnets, in which the first magnetic bodies are arranged around the rotational axis at regular intervals, and the first permanent magnets are each arranged between the neighboring first magnetic bodies in a circumferential direction, and the first permanent magnets are all magnetized outward, and magnetic poles thereof are made identical; the second rotor has second magnetic bodies and second permanent magnets, in which the second magnetic bodies are arranged around the rotational axis at regular intervals, and the second permanent magnets are each arranged between the neighboring second magnetic bodies in the circumferential direction, and like directions of the magnetic poles of the first permanent magnets, the second permanent magnets are all magnetized outward, and magnetic poles thereof are made identical; the stator has third magnetic bodies that protrude inward in a radial direction and which are provided with slots in which coils can be wound, the coils being wound around the third magnetic bodies, and third permanent magnets, in which the third magnetic bodies are arranged around the rotational axis at regular intervals and the third permanent magnets are each arranged between the neighbouring third magnetic bodies in the circumferential direction, and like directions of the magnetic poles of the first permanent magnets, the third permanent magnets are all magnetized outward, and magnetic poles thereof are made identical; and a relationship of Ns = Nl±Nh is satisfied when Nl is the number of magnetic poles of the first rotor, Nh is the number of pole pairs of the second rotor, and Ns is the number of slots of the stator.