CuB/SiO2 and Cr-CuB/SiO2 catalysts were prepared using the impregnation-chemical reduction method and examined for the hydrogenation of furfual, crotonaldehyde and citral. The ultrafine catalysts of CuB could be effectively stabilized on SiO2 for the liquid-phase hydrogenations, the optimal copper loading was 10%, and the resulting CuB/SiO2 catalysts were much more active than the generally supported catalyst of Cu/SiO2. Copper dispersion and CuB stability on SiO2 were enhanced by chromium doping. Moreover, the chromium effectively promoted the reduction of the single C=O group, such as furfural, and the conjugated C=C/C=O groups, such as crotonaldehyde and citral, with the optimal doping amount being 15%. The 15% Cr-CuB/SiO2 catalyst was much more active than the commercial copper chromite for the reduction of the single C=O group, and its level of activity was comparable to that of copper chromite for the reduction of the conjugated C=C/C=O groups. The single C=O group reduced more easily than the single C=C group for the copper-based catalysts, but delocalization between the conjugated C=C and C=O bonds facilitated the reduction of the C=C bond. Nevertheless, the stereo hindrance of the substitute on the conjugated C=C bond may have overwhelmed the delocalization effect and favored the reduction of the conjugated C=O bond.