Effects of various additives have been investigated on physical and chemical properties of aluminium titanate based ceramics within the Al2O3-TiO2-MgO and the Al2O3-TiO2-Fe2O3 systems. Conversion of aluminium. titanate and physical properties thereof has also been studied as a function of quantity of additives. The experiments proved that there is a strong relationship between incorporation of additives in the crystal structure of Al2TiO5 and the rate of conversion as well as the development of physical properties. Steady increase of lattice parameters and the determined phase compositions indicated that Mg2+ and Fe3+ ions form a complete miscibility solid solution with the above compound.