Disclosed is an exhaust gas purifying catalyst in which grain growth of a noble metal particle supported on a support is suppressed. Also, disclosed is a production process of an exhaust gas purifying catalyst, by which the above exhaust gas purifying catalyst can be produced. The exhaust gas purifying catalyst comprises a crystalline metal oxide support and a noble metal particle supported on the support, wherein the noble metal particle is epitaxially grown on the support, and wherein the noble metal particle is dispersed and supported on the outer and inner surfaces of the support. The process for producing an exhaust gas purifying catalyst comprises masking, in a solution, at least a part of the surface of a crystalline metal oxide support by a masking agent, introducing the support into a noble metal-containing solution containing a noble metal, and drying and firing the support and the noble metal-containing solution to support the noble metal on the support.