The effect of the Co doping on the structure, electrical conductivity and electrochemical properties of Sr(0.8)Ce(0.2)MnO(3-delta) was investigated. The Co doping decreased the sintering temperature by about 100 degrees C and cubic structure was synthesized for Sr(0.8)Ce(0.2)Mn(0.8)Co(0.2)O(3-delta). The electrical conductivity of Sr(0.8)Ce(0.2)Mn(0.8)Co(0.2)O(3-delta) reached 102 S cm(-1) at 700 degrees C, which was sufficient to provide low ohmic losses at the cathode. In comparison with Sr(0.8)Ce(0.2)MnO(3-delta), the area-specific resistance of Sr(0.8)Ce(0.2)Mn(0.8)Co(0.2)O(3-delta) was 0.10 Omega cm(2) at 750 degrees C, which was about 20 times lower than that of Sr(0.8)Ce(0.2)MnO(3-delta). While the exchange current density i(0) of Sr(0.8)Ce(0.2)Mn(0.8)Co(0.2)O(3-delta) was 0.49 A cm(-2) at 800 degrees C, that for Sr(0.8)Ce(0.2)MnO(3-delta) was 0.11 A cm(-2). The results show that the Sr(0.8)Ce(0.2)Mn(0.8)Co(0.2)O(3-delta) cathode had high catalytic activity for oxygen reduction reaction in the temperature range of 700-800 degrees C. Crown Copyright (C) 2008 Published by Elsevier Ltd on behalf of International Association for Hydrogen Energy. All rights reserved.