The polycrystalline ferrites Mn-Zn-Ca have been prepared using by conventional ceramic technique, sintered at 1200 C for 4 hours. In this project, I have studied the microstructure, magnetic and electrical properties of Mn-Zn ferrites with and without additives. Investigations have been carried out by the measurements of density, microstructure, Curie temperature, permeability, loss factor, Q-factor, resistivity and dielectric constant of the samples.Curie temperature of the samples have been found to be increase with Mn addition and decreased with Ca-addition. Initial permeability increases...