Abstract: The catalytic oxidation traps seem to be one of the best ways for diesel particulate removal from exhaust gases thanks to their simplicity, easy handling, high abatement efficiency and comparatively low cost.The catalyst contained in such device should lower down soot ignition temperature to the values characteristic of diesel exhaust (180～350 ℃).This paper concerns the development of catalyst for catalytic oxidation traps.Sn catalyst was loaded on TiO₂ and γ-Al₂O₃-coated cordierite honeycomb and the catalysts were modified by Cu,K,V.The catalysts were activated in air in a muffle oven at 700℃ for 3 h.Catalyst activity was checked through DSC/TG experiments.Sn catalysts remarkably decreased soot ignition temperature and enlarge combustion temperature range.Along with adding Cu,K,V, the ignition temperature made further decrease and combustion temperature range narrowed slightly.The activation processes resulted in activity decrease.The reason for activity decrease was not caused by sintering,but by lapse of activity component.