A series of mixed oxide catalysts with different composition of Co-M-Al and Co-M-Ce-Al (M=Zn, Ni, Cu) were prepared by co-precipitation method from hydrotalcite-like compounds. The experimental results revealed the catalytic activity of Co-Ni-Al is slightly higher than that of Co-Zn-Al and much higher than that of Co-Cu-Al for direct decomposition of N2O. Moreover, addition of small amounts of CeO2 improved the catalytic activity significantly and made the decomposition temperatures at which the N2O conversion was 50% and 90% (T50 and T90) both decreased 80 °C than those of Co-M-Al catalysts without CeO2 added. Further, potassium-load also promoted the catalytic activity, and the decomposition temperatures of T50 and T90 both decreased approximately 50 °C. It is significant for decomposing N2O from industries and reducing carbon emission from atmosphere.