Nano particles of cerium tungsto iodate, a tetravalent metal acid salt, have been prepared by chemical co-precipitation method. The particle size of the sample has been calculated from its X-ray diffraction pattern and the average grain size is found to be 25 nm. The size is further characterized by SEM, TEM and FTIR analyses. Its dielectric behaviour at various temperatures (50 degrees-110 degrees C) and frequencies is also investigated. The dielectric constant values increase with the decrease in frequency and the increase in temperature. Moreover, the sample in its protonated form is subjected to ion exchange capacity studies. The data reveals that the sample works as a good ion exchanger.