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Liquid-phase sintering method was used to prepare BaTiO3 powders and the structure and electrical properties of (1-x)BaTiO3+(x)La2/3Sr1/3MnO3 (LSMO) composites were investigated. The results of X-ray diffraction showed that the prepared BaTiO3 powders were pure and fine,indicating that sintering temperature was effectively lowered when the NaCl sintering aid was added.X-ray diffraction patterns of (1-x)BaTiO3+(x)La2/3Sr1/3MnO3 (LSMO) composites showed that LSMO and BaTiO3 phases were coexistent and no other phases were detected.The impedance spectra showed that the resistance of grain boundaries for LSMO-doped samples was suppressed. The resistivity-temperature measurements showed that roomtemperature resistivity of the composites was lowered from insulator for pure BaTiO3 ceramic to 103 Ω·m for the x=0.3 sample.The sample of x≤0.2 showed the positive temperature coefficient (PTC) effect whereas the x=0.3 sample exhibited PTC effect at temperatures below 68 ℃ and then negative temperature coefficient (NTC) effect at temperatures above 68 ℃.The related mechanism has been elucidated.