The melting temperatures of lithium niobate (LN:LiNbO3) sintered powders of varying composition were measured under an electric field by an in-house-made DTA capable of applying an electric field. For non-doped LN (X-Li = [Li]/[Li]+[Nb] = 0.460-0.500), the congruent point moved away from the stoichiometric composition under an external electric field, while the congruent point may have moved toward the stoichiometric composition when 6.0 mol% Mg was added to LN. The temperature change for 0-10 mol% Mg-doped c-LN is also shown and the maximum temperature change (similar to 3 degrees C) was observed at 6.0 mol% doping. (C) 2008 Elsevier B.V. All rights reserved.