A　series　of　Pd/delta,　theta-Al2O3　catalysts　containing　BaO　for　anthraquinone　hydrogenation　to　produce　H2O2　were　prepared　by　the　impregnation　method.　The　effect　of　barium　oxide　on　the　performance　of　Pd/delta,　theta-Al2O3　catalyst　was　investigated　by　X-ray　diffraction,　scanning　electron　microscopy,　nitrogen　adsorption,　H2O2　titration,　and　electron　probe　microanalysis　techniques.　The　results　showed　that　barium　oxide　was　a　good　promoter　of　the　Pd/delta,　theta-Al2O3　catalyst　for　the　reaction.　The　addition　of　a　proper　amount　of　barium　oxide　could　inhibit　the　growth　of　alumina　crystals　at　high　temperature,　increase　the　catalyst　surface　area,　improve　the　Pd　dispersion,　increase　the　Pd　concentration　on　the　catalyst　surface,　and　decrease　the　Pd　layer　thickness.　The　addition　of　3　BaO　increased　the　catalyst　activity　by　about　25%.