Disclosed is an exhaust gas purifying catalyst, which comprises an oxygen absorbing material having a catalytic noble metal arranged at a lattice position or an interlattice position of a crystal structure of a composite oxide containing Ce and Zr, which is capable of sufficiently exhibiting a catalytic function even if a ZrO2 mass ratio is out of the range of 20 to 30 mass % or 65 to 90 mass %. Specifically, in an exhaust gas purifying catalyst formed with a catalyst layer including a cerium-zirconium (CeZr) composite oxide, the composite oxide contains ceria (CeO2) and zirconia (ZrO2) in such a manner that a mass ratio of ceria to a total mass of ceria and zirconia falls within the range of 36 to 64 mass %. Further, the composite oxide contains, in the form of an oxide, a rare-earth metal other than cerium (Ce), in the range of 3 to 20 mass % with respect to a total mass of the composite oxide.