The catalytic N2O decomposition was investigated over a series of NiCe mixed oxides. Characterizations of XRD, N-2-adsorption, SEM, XPS, and H-2-TPR were applied to correlate their properties with the corresponding catalytic performance. The catalyst Ni90Ce10 prepared by citrate acid method exhibited the highest catalytic activity among the mixed oxides, which could completely decompose N2O at 400 degrees C in the presence of oxygen. The introduction of CeO2 could prevent the agglomeration of NiO and preserve high surface area. A strong interaction between NiO and CeO2 was observed in the mixed oxides; the interaction enhanced oxygen mobility and resisted the inhibition of O-2.