Cation layered perovskite-related oxides, NdBa1-xSrxCo2O5+delta oxides, have been considered as cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs) on the basis of their superior electrochemical properties. The aim of this study is to identify the effect of Sr doped NdBa1-xSrxCo2O5+delta oxides by investigating their structural, electrical, and electrochemical performance. The electrical conductivities are enhanced with increasing Sr content due to the greater amount of electronic holes originating from the increased interstitial oxygen. The maximum power densities of NdBa1-xSrxCo2O5+delta increase with Sr content up to x = 0.75, but show a sudden drop at x = 1.0. Therefore, x = 0.5 and x = 0.75 in NdBa1-xSrxCo2O5+delta oxides are desirable candidate cathode materials in IT-SOFC in terms of electrochemical performance. (C) 2013 Elsevier Ltd. All rights reserved.