EXHAUST GAS PURIFICATION CATALYST

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An ability of oxidizing CO and HC is improved, while achieving a sufficient efficiency of burning PM. An exhaust gas-purifying catalyst includes a filter substrate (1) in which upstream and downstream cells (13a, 13b) separated by a porous wall (11) are formed, the upstream cell (13a) being open on an upstream side of the filter substrate (1) and closed on a downstream side of the filter substrate (1), and the downstream cell (13b) being closed on the upstream side and open on the downstream side, a precious metal supported by the filter substrate (1), and an alkaline metal and/or alkaline-earth metal supported by the filter substrate (1). A support amount of the alkaline metal and/or alkaline-earth metal per unit volume of the filter substrate (1) is greater in an upstream section (1a) of the filter substrate (1) than in a downstream section (1b) of the filter substrate (1).