A combination of two base-metal oxides in tandem con guration can realize three-way reaction without platinum group metals. For this purpose, catalysts for hydrocarbon preferential oxidation (HC-PROX) and for NO reduction by CO are required. For the design of HC-PROX catalysts, competitive oxidation of propene and CO on spinel-type MFe 2 O 4 (M= Co, Cu, Mg, Mn, Ni, Zn) was investigated. MnFe 2 O 4 preferentially oxidized propene in the co-presence of CO showing the best propene oxidation activity.Among the series of MFe 2 O 4 , the activity controlling factor was correlated to the M-O bond energy of the second metal oxides, and the HC preferential oxidation property was dependent on the electronegativity of the second ion. A tandem catalyst using MnFe 2 O 4 for HC-PROX and CuCo 2 O 4 for NO-CO reaction showed TWC activity comparable to a Rh/CeO 2 .