The present invention provides a metal oxide particle for a catalyst support comprising multiple species of metal oxides and capable of satisfactorily exerting the properties of the respective metal oxides, and also provide a production process therefor and an exhaust gas purifying catalyst obtained from this metal oxide particle. A metal oxide particle of the present invention comprises a core part 1 relatively rich in a first metal oxide and a surface layer 2 relatively rich in a second metal oxide, the core part and the surface layer each comprising a plurality of primary particles (1a, 2a), and the primary particle diameter of the second metal oxide being smaller than the primary particle diameter of the first metal oxide.