EXHAUST GAS PURIFICATION CATALYST

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Provided is a technology that is advantageous in increasing NOx purification performance after long-term use. A provided exhaust gas purification catalyst (1) contains : particles (31) comprising an oxygen-storage material; particles (32) that are disposed between the oxygen-storage particles (31) and that comprise at least one rare-earth element other than cerium, and/or compounds thereof; and particles (33) that are disposed between the oxygen-storage particles (31) and that comprise at least one noble metal. The characteristic X-ray intensity spectrum of one of the rare earth elements and the characteristic X-ray intensity spectrum of one of the noble metal elements, as obtained by energy-dispersive X-ray spectrometry analyzed over a length of 500 nm, have a coefficient of correlation of at least 0.68.