An efficient conversion of biomass-derived cyclohexanone to cyclohexanol by in situ-formed hydrogen over Cu catalyst under hydrothermal conditions was reported at first. Among the catalysts tested, Cu exhibited high catalytic activity for the conversion of cyclohexanone, and the highest yield of 100% was obtained when Zn acted as reductant. The experiment was carried out by using gaseous hydrogen as the external hydrogen source indicated that the yield of 75.1% was lower than in situ-formed hydrogen by oxidation of Zn in water. The present study provides an efficient route by environmentally benign, commercially available Cu powder as a catalyst for cyclohexanone conversion to cyclohexanol. (C) 2015 Elsevier B.V. All rights reserved.