CeO2 and CuOx-CeO2 supported potassium catalysts were synthesized by wetness impregnation method.The catalysts were characterized by BET,NO-TPO,NOx-TPD and soot-TPO measurements.By the decoration of potassium and copper,the maximum soot combustion temperature of the ceria-based catalyst decreased to 338 and 379 ℃ in the presence and absence of NO under a loose contact mode,respectively.The pronouncedly enhanced NO oxidation ability by copper introduction and NOx storage capacity by potassium modification were especially important in the NOx-assisted soot oxidation reaction with the K/CuCe catalyst.