Abstract: A series of Pd-MnOx/SiO2-Al2O3 catalysts with different MnOx contents ha d excellent performance of decomposing O3 at high GHSV, low temperature，and l o w concentration. Especially on the catalysts with MnOx content of 80% -90%, T100, the complete conversion temperature, was i n the range of 45-50 ℃, which can meet the decomposition temperat ure of O3. These catalysts had high capacity to resist deactivation.

Key words: ozone, manganese dioxide with deficient oxygen atom, palladium, catalytic decomposition, monolith catalyst