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A series of Au/CuMn catalysts was prepared via a deposition-precipitation method and characterized by X-ray diffraction (XRD) and X-ray photoelectron spectra (XPS) techniques. The influences of Au loadings and the calcination temperature on the catalytic activity of Au/CuMn catalyst were investigated. The results demonstrate that the catalyst with 3% Au loading obtained at the calcination temperature of 60 oC exhibits the highest activity, i.e. 72.4% NO conversion at the reaction temperature as low as 50 oC, but the deactivation soon occurs. XPS analysis reveals that Au3+ and Oads. presenting on the catalyst surface are active centers and play an important role. The deactivation during reaction process is related with the partial reduction of both oxidized gold species and Oads. species on the surface of the catalysts. Furthermore, the covering of catalyst surface by carbonate, nitrates and formate formed during catalytic operation is another reason of deactivation