The invention provides a magnetic ring rotor assembly and a motor. The magnetic ring rotor assembly comprises a rotor (1) and a magnetic ring (2), wherein the magnetic ring (2) sleeves the rotor (1),a circumferential limitation structure and an axial limitation structure are formed between the rotor (1) and the magnetic ring (2), the circumferential limitation structure is used for limiting circumferential relative positions of the rotor (1) and the magnetic ring (2), the axial limitation structure is used for limiting axial relative positions of the rotor (1) and the magnetic ring (2) and preventing the magnetic ring (2) from separating from the rotor (1), and the circumferential limitation structure and the axial limitation structure are matched with each other so as to prevent relativemotion of the rotor (1) and the magnetic ring (2). In the magnetic ring rotor assembly provided by the invention, a process of connecting and fixing the rotor and the magnetic ring is simple, and themagnetic ring rotor assembly is high in reliability and relatively low in cost.