<p>In this paper, Mn-Zn ferrites doped with Rare-Earth (RE) ions of Gd³⁺, Ho³⁺, and Yb³⁺ were prepared by the solid-state sintering process in an air atmosphere, and their crystalline structure, morphology and magnetic properties were systematically investigated. The results of XRD and FTIR confirmed that the as-prepared samples were pure phase with the typical spinel structure of Mn-Zn ferrite. Furthermore, RE-ions doping resulted in the lattice expansion of Mn-Zn ferrite. SEM analysis showed that RE-ions doping would make Mn-Zn ferrite ceramic more homogeneous and denser. The effect of RE-ions doping on the magnetic properties of Mn-Zn ferrite was investigated by VSM and impedance analyzer. It was found that RE-ions doping did not change the soft magnetic nature of Mn-Zn ferrite too much. However, RE-ions doping did increase the permeability (real part <i>μ′</i>) and weaken the coercive field of Mn-Zn ferrite, making it more susceptible to magnetization. Herein, a possible mechanism for the improvement in the magnetic properties of Mn-Zn ferrite due to RE-ions doping was proposed. Admittedly, the substitution of Fe³⁺ by RE ions with larger magnetic moments (Gd³⁺ and Ho³⁺) can enhance the permeability of Mn-Zn ferrite. However, the small magnetic moment and large radius RE ion (Yb³⁺) dopant enhancing the permeability of Mn-Zn ferrite could only be attributed to the fine variations in crystalline structure (<i>eg.</i>, lattice expansion or distortion of oxygen octahedron). Such fine variations might adjust the angle and distance of magnetic exchange interaction to enhance magnetic coupling, thereby improving the magnetic properties of Mn-Zn ferrite. It is believed that achievements in this case open up a new idea for enhancing the magnetic properties of Mn-Zn ferrites through structure modulation, which is more favorable for its practical application in the field of soft magnetic materials in the future.</p>