Cerium-iron mixed oxides were prepared by a glycothermal method, and NO decomposition reactions over these oxides and barium catalysts supported on them were examined. Although Ce-Fe mixed oxides (Ce-Fe(x), x = Fe/(Ce + Fe) molar ratio) exhibited only low activities for the direct decomposition of NO into N-2 and O-2, Ba catalysts supported on these mixed oxides are active for this reaction. The highest NO conversion was achieved with 3 wt% BaO/Ce-Fe(0.02). The NO conversion on this catalyst increased with increasing reaction temperature, and NO conversion was 51% at 800 degrees C. The high activity of this catalyst was maintained for more than 10 h and a relatively high NO conversion (23%) was obtained even in the presence of 5% oxygen. The XRD results indicated the formation of Ce-Fe(x) solid solutions with a cubic fluorite structure. The CO2-TPD results indicated NO decomposition activities of the catalysts were correlated with their basicities.