Tlıe corrosion behaviour of the prepared Materials was studied by mcans of weight-loss techniquc in stagnant solution of (0.01 M) sulphuric acid in presence of thiourea as an inhibitor. Higher concentration of thiourea reduces the corrosion rate of thc samples and proteetion effi- cicncy of thiourea was found to be 80 % for ferrites Proteetion is mainly due to adsorption. Corrosion rate inereases with inereasing tcmperaturc. According to Bockris-Swinkels isotherm, one molecule of vater is displaced by five thiourea molecules on the surface. Thermodynamic data for the adsorption process △H0 and /\S° were also calculated and dis- cusscd.