Abstract: The experiments have been performed to investigate the grain growth, the characterization of grain boundary migration and the interfacial phenomena at high temperature for Fe-25Cr-5Al-RE alloy. The results show that the rare earth (landium is main) has a certain effect on the grain growth of alloy; La₂O₃ may be the nuclear center of titanium nitride phases that precipitate in the matrix of the alloy; for Fe-Cr-Al-RE (RE<0.1%) fine titanium nitride may precipitate on the grain boundaries and inhibite the migration of grain boundaries; by repeated heating and cooling, the rare earth increases the permeation of O^2- ions through the oxide scale, lanthanum atoms diffuse towards the interfaces and precipitate as lanthana. There is no doubt that the precipitates lanthana and alumina in matrix as a trapping of vacancies greatly increase the oxidation resistance and the life of the electric heating alloy.