Supported Ni–B and Ni–B–K amorphous alloy catalysts were prepared by chemical reduction method and characterized by nitrogen adsorption–desorption, power X-ray diffraction, selected area electron diffraction, and scanning electron microscopy. The prepared catalysts were tested in liquid phase hydrogenation of adiponitrile in the absence of ammonia under mild condition. Ni–B–K/SiO2 exhibited high activity and selectivity toward 6-aminocapronitrile and 1,6-hexanediamine.