A series of Cu substituted Mg-Zn ferrite powders MgCu Zn Fe O with , 0.1, 0.2, 0.3, 0.4 were synthesized by chemical co-precipitation method. The structure and magnetic behavior of the powders are investigated by x-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The results show that all the samples annealed at 600 C are pure spinel phase and the copper content has an obvious influence on coercivity (Hc), saturation magnetization (Ms) and the lattice constant . The densification characteristics and magnetic properties of the low-temperature sintered Mg Cu Zn Fe O ferrites were also investigated. The density of sintered samples is observed to increase monotonously with Cu content. At the same time, the initial permeability is observed to increase with increase in copper content up to followed by a decrease, while the Curie temperature (Tc) increase continuously from 125 C to 190 C when x increases from 0.0 to 0.4. Index Terms-Chemical co-precipitation method, initial permeability, low temperature sintered, Mg-Cu-Zn ferrite.