EXHAUST GAS PURIFICATION CATALYST DEVICE

An exhaust gas purification catalyst device 10 which comprises: a lower layer 1 which contains metal oxide particles MO, and Pd and Pt supported by the metal oxide particles MO; and an upper layer 2 which contains zirconia-containing metal oxide particles ZrO, and Rh supported by the zirconia-containing metal oxide particles ZrO. This exhaust gas purification catalyst device 10 is configured such that: the lower layer 1 comprises a lower layer first stage part If that is on the exhaust gas upstream side, and a lower layer second stage part 1r that is on the exhaust gas downstream side; the lower layer first stage part 1f contains 1.8 g/L or more of Pd and 0.05 g/L or more of Pt; the lower layer second stage part 1r contains 0.10 g/L or more of Pd, while containing no Pt or 0.10 g/L or less of Pt; the amount of the zirconia-containing metal oxide particles ZrO in the upper layer 2 is from 60 g/L to 140 g/L (inclusive); and the amount of Ce in the upper layer 2 in terms of CeO2is 7g/L or less.