Cryptomelane type manganese oxide K-OMS-2 and Ni-Ce-OMS-2 co-doping materials were synthesized by one-step preparation with refluxing system. The crystalline structure, and morphology were characterized by X-ray diffraction analysis and SEM images. Ni (II) and Ce (III) were incorporated into cryptomelane, substituted for Mn (III) and Mn (IV) resulting an increase of Mn-average-oxidation-state from 3.6 to 3.8 for un-doped and co-doped samples, respectively. With different amount of precursor-cerium concentration, NiCe1.0 improved the ethanol conversion by a factor of 8 compared to unmodified K-OMS-2. Additionally, NiCe1.0 showed a significant increase of ethanol conversion with reaction temperature. Over above 90% of ethanol was total oxidized at 150 C suggesting a potential Ni-Ce-OMS-2 catalyst for removing volatile organic compounds at low temperature.