The crystal structure and electrical conductivity of Ba-2(Fe1-xInx)(2)O-5 were studied. It was found that Ba-2(Fe1-xInx)(2)O-5 has the cubic perovskite structure with disordered oxygen vacancies at room temperature. The variation of the molar volume with the In3+ content obeyed Vegard's law, indicating that In3+ was successfully substituted into Fe3+ sites at random. Thermogravimetry-differential thermal analysis revealed that Ba-2(Fe1-xInx)(2)O-5 (x not equal 0, 1) does not undergo structural phase transitions between room temperature and 1200 degrees C under a N-2 flow. The electrical conductivity was measured by the four-probe method under a N-2 flow. Although the types of conductivity were not clearly determined, the conductivity for x = 0.1 exhibited the maximum value of more than 10(-1) S/cm above 600 degrees C (C) 2015 Elsevier B.V. All rights reserved.