Preparation, thermal expansion, electrical conductivity and polarization of La0.6Sr0.4C1-xGaxO3-delta (LSCG) (x=0.0-0.4) were studied in order to estimate the potential as a new material for cathode of intermediate temperature solid oxide fuel cells (ITSOFC). Within xless than or equal to0.4, hexagonally distorted perovskite single phase of La0.6Sr0.4Co1-xGaxO3-delta was obtained. Thermal expansion coefficients (TEC) of the specimens with x<0.3 showed higher values than those of electrolyte materials, such as Ce0.8Gd0.2O1.9 or La0.8Sr0.2Ga0.85Mg0.15O2.825, whereas those of specimens with x=0.3 showed close value. The electrical conductivity decreased with increasing Ga content; however, the conductivity for x=0.4 is still in the order of 10(2) S/cm at 800 degreesC. Polarization measurements showed that cathode performance decreased with increasing Ga content; however, the sample with x=0.4 still has sufficient activity as a new cathode material of ITSOFC. (C) 2004 Elsevier B.V. All rights reserved.