This work was aimed to design efficient catalysts for N 2 O decomposition at low temperatures. Cobalt oxide (Co 3 O 4) was prepared by hydrothermal, precipitation and combustion methods and tested for N 2 O decomposition. It was found that the catalysts prepared by solution combustion synthesis were most active for this reaction. Subsequently, a series of ceria (CeO 2) supported Co 3 O 4 catalysts (xCeCo) were prepared by solution combustion method and used them for N 2 O decomposition. All the catalysts were characterized by analytical methods like XRD, TEM, BET, XPS, UV-Vis, Raman and H 2-TPR. It was found that 10 and 20 wt..% loading of CeO 2 on Co 3 O 4 promoted the activity of Co 3 O 4 towards N 2 O decomposition, whereas, higher loading of CeO 2 reduced the activity. Typical results indicated that addition of CeO 2 increases the surface area of Co 3 O 4 , and improves the reduction of Co 3+ to Co 2+ by facilitating the desorption of adsorbed oxygen species, which is the rate-determining step for the N 2 O decomposition over Co 3 O 4 spinel catalysts. Optimal CeO 2 loading can increase both dispersion and surface area of Co 3 O 4 catalysts and weaken the CoO bond strength to promote N 2 O decomposition.