Ni _0.4-x Cu _x Zn _0.6 Fe ₂ O ₄（x＝0， 0.12， 0.20， 0.28） ferrite was prepared by the traditional ball milling method. The  microstructure， phase composition and magnetic properties of Ni-Zn ferrite with CuO doping on were investigated by scanning electron microscope （SEM）， X-ray diffraction （XRD）， comprehensive thermal analysis （TG-DSC） and vibrating sample magnetometer （VSM）. The results showed that with the increase of CuO content， the second phase of Ni-Cu-Zn ferrite was formed， and the diffraction peak intensity of Ni-Cu-Zn ferrite gradually increased. It could be seen from the microstructure and energy spectrum that Cu ^2＋ participated in the reaction of ferrite. The increase of CuO content improved the sintering performance of the sample， and reduced the crystallization temperature of Ni-Cu-Zn ferrite. The hysteresis loop showed soft magnetic properties of Ni _{0.4- x} Cu _x Zn _0.6 Fe ₂ O ₄ （x＝0， 0.12， 0.20， 0.28）. When the CuO content x was 0.2， the saturation magnetization （M _s） of ferrite was highest. Meanwhile， the coercive force （H _c） was relatively low.