WASTE GAS PURIFICATION CATALYST

PROBLEM TO BE SOLVED : To produce a waste gas purification catalyst exhibiting a high HC (hydrocarbon) cleaning performance. SOLUTION : This waste gas cleaning catalyst comprises a carrier layer and a catalyst noble metal. Therein, the carrier layer contains aluminum, cerium, zirconium and at least one kind of rare earth element. The catalyst noble metal is platina, palladium and rhodium and a weight ratio of Pt : Pd : Rh is 2-10 : 20-30 : 0.5-2. The waste gas purification catalyst has the excellent purification performance of HC component by controlling the weight ratio between the component contained in a porous body constituting the carrier layer and the catalyst noble metal.