EXHAUST GAS CLEANING CATALYST

The present invention provides an exhaust gas cleaning catalyst 10 comprising : a substrate 11; a reforming reaction layer 20 which is provided on the substrate and which includes at least one of a rare-earth oxide and a transition metal oxide (excluding noble metals other than Rh, Ru), the reforming reaction layer serving as a hydrogen-generating catalyst for converting unburned components in an exhaust gas into H2; and a catalyst layer 30 including a noble metal that cleans the unburned components. The content of the hydrogen-generating catalyst in the reforming reaction layer 20 per unit volume of the substrate 11 is 5 g/L or more.