The exhaust gas purifying catalyst

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PROBLEM TO BE SOLVED : To obtain an exhaust gas cleaning catalyst that retains its high catalytic activity even after exposure to a high temperature and acts effectively even at a relatively low temperature. SOLUTION : A coating layer containing a cerium-base multiple oxide of the formula Ce1-(x+y)ZrxMyO2-z on which platinum and rhodium have been supported and a zirconium-base multiple oxide of the formula Zr1-(a+b)CeaNbO2-c on which platinum and rhodium have been supported is formed on a heat resistant carrier to obtain the objective exhaust gas cleaning catalyst. In the formulae, M and N are each an alkaline earth metal or a rare earth element other than cerium and zirconium, 0.35<=1-(x+y)<=0.80, 0.20<=x<=0.65, 0.65<1-(a+b)<=0.90, 0.10<=a<=0.35, (z) is the deficiency of oxygen defined by the oxidation number of M and atomic ratio and (c) is the deficiency of oxygen defined by the oxidation number of N and atomic ratio.