Provided is a novel catalyst carrier for exhaust gas which relates to an OSC material containing a ceria-zirconia composite oxide and is able to enhance the low temperature properties and to exert excellent OSC even at the time of engine start and excellent exhaust gas purification performance. A catalyst carrier for exhaust gas containing a fluorite type ceria-zirconia composite oxide and ceria formed from the fluorite type ceria-zirconia composite oxide by phase separation proposed.