Abstract Effect of the substitution by two ions together, (Ti-Mg) ions, on the structure, magnetic and electrical properties of Ni - Zn ferrite of chemical formula Ni0.7 Zn0.3 (Mg Ti)x Fe2-xO4 (x = 0, 0.1, 0.2, 0.3and 0.4) prepared by conventional ceramic method. These structure of the prepared samples was studied using X– ray diffraction pattern. It was found that as (Mg-Ti) ions concentration increases, the value of saturation magnetization, initial permeability and Curie temperature were decreased. It was also observed that the dc resistivity of the prepared samples increased with increasing (Mg-Ti) concentration and hence decreasing the dielectric loss of investigated samples. The present study indicated also that the samples of x = 0.1 and 0.2 show high resistivity and relatively high magnetic properties which can be exploited in a certain technical application.