Abstract: A class of multiphase rubidium titanate functional ceramic materials is provided in this disclosure, the composition of which comprises phases of rubidium n-titanates with chemical formula of Rb2TinO2n+1, that of titanium dioxide with chemical formula of TiO2, and a small amount of optional dopant for the purpose of further improving or adjusting performance of the materials. The said materials are obtained by mixing the sources of rubidium, titanium and optional dopant to get a highly active fine-powdery precursor, and then by making heat-treatment in air of the precursor. The said materials possess unusual electrical and electrochemical properties, such as colossal permittivity up to the order of 109 at room temperature accompanied by relatively low dielectric loss, excellent insulativity accompanied by high ionic conductivity up to 10?3 S/cm, have a broad application prospect in the fields like rechargeable high energy density storage devices, semiconductor devices and catalytic purification.