A Cu-based catalyst was developed for one-step solvent-free synthesis of aviation biofuel from biomass-derived ketones, including acetone, cyclopentanone, cyclohexanone, and 2-pentanone. Under the optimal working conditions, the conversion rate of acetone, cyclopentanone, cyclohexanone and 2-pentanone of 100% can be achieved by using Cu/Al2O3. 79.7 c% maximum carbon yield of liquid hydrocarbons with 89.5% selectivity of aviation biofuel was obtained under the conditions of 1.0 MPa H-2, 280 degrees C, and 2 h(-1) WHSV. The effects of the calcination temperature on the acidity and basicity of the catalyst, as well as the valence and dispersion of Cu species, were investigated. Based on DFT calculations and in situ DRIFTS results, the preferred adsorption of carbonyl groups and efficient dissociation of hydrogen on Cu+ increased the local concentration of H and feedstock on the catalyst surface, accelerating the rate-determining step that predominated on Cu-0. The synergistic effect of Cu-0 and Cu+ enhanced the formation of aviation biofuel.