The catalytic combustion of dibenzofuran and chlorobenzene, model compounds for dioxin, was investigated on Pt supported zeolite catalysts. Among transition metals, such as Pd, Au, Ni, etc., Pt supported on H-USY zeolite was the most active and stable for the combustion of dibenzofuran into CO2 and water at 573 K. The reduction treatment on Pt/H-USY before the reaction gave high activity compared with the oxidation treatment. The con version of dibenzofuran was governed by the dispersion of Pt particles irrespective of the acidity and porosity of support materials including zeolites, mesoporous silica and silica gel. The combustion of chlorobenzene on Pt/ zeolite proceeded at much higher temperature than that of benzene. The conversion of chlorobenzene was accel erated by the presence of water vapor in the reactant and the acid sites on zeolite. The activity of Pt/H-ZSM-5 for the combustion of polychlorodibenzofuran, one of dioxin, was discussed from the combustion results of dibenzofuran, chlorobenzene and benzene.