PURPOSE: To improve the heat-resistance and durability of a catalyst, by providing an oxide layer at a place where the catalyst is supported in a combustion chamber, and by dipping the oxide layer in a mixed solution of plural kinds of catalysts to simultaneously support the plural kinds of catalysts.

CONSTITUTION: To support a catalyst on at least part of an auxiliary chamber wall defining the combustion chamber of a diesel engine, a glow plug, a piston's top or the like, an oxide layer is provided at a place where the catalyst is to be supported in the combustion chamber. The oxide layer is thereafter dipped in a mixed solution of plural kinds of catalysts so that the plural kinds of catalysts are simultaneously supported by the oxide layer. Zirconium oxide or the like is used as the oxide layer, which is provided in a method such as melt- spraying. Platinum and rhodium, or the like are used as the plural kinds of catalysts, which are mixed together to prepare the mixed solution. According to this constitution, the heat-resistance and durability of the catalyst are enhanced.