0.9Pb(Zn1/3Nb2/3)-0.1BaTiO(3) (0.9PZN-0.1BT) of perovskite structure has been successfully prepared by mechanically activating mixed oxides of PbO, ZnO, Nb2O5, BaO and TiO2. The novel mechanochemical technique skips the phase-forming calcination step at an intermediate temperature that is always required in both the conventional solid state reaction and chemistry-based precursor routes. Ultrafine 0.9PZN-0.1BT particles of perovskite structure were formed when the constituent oxides were mechanically activated for more than 10 h. The powder was sintered to a density of 96% theoretical density at 1100 degrees C for 1 h. The sintered 0.9PZN-0.1BT exhibits perovskite structure and a peak dielectric constant of 8800 at the Curie temperature of 60 degrees C when measured at a frequency of 100 Hz.