? The Royal Society of Chemistry 2015. To achieve high power density in intermediate-temperature solid oxide fuel cells (IT-SOFCs), we introduce a dense La(Sr)Fe(Mn)O3-δ (LSFM) nano-film anode between a Ni-Fe metallic substrate and a LaGaO3-based oxide electrolyte. Although a three-phase boundary (TPB) is believed to be required for anode active sites, the cell with the LSFM mixed-conductor thin-film anode exhibited much improved power density compared with that of the cell with a simple porous Ni-Fe anode. The maximum power density of the cell with the LSFM film was approximately 3.0 W cm-2 at 973 K. The improved power density was primarily attributed to the enhanced anodic activity. Furthermore, we observed that the dense LSFM thin-film anode is effective in increasing the fuel utilization of a Ni-Fe metallic anode supported cell. This suggests that a two-phase boundary (anode and gas phase) at the LaFeO3 perovskite is highly active towards the anodic reaction.