AbstractHydrogen evolution reaction (HER) coupled with biomass conversion is a sustainable route to produce clean energy H2 and value‐added chemicals simultaneously. Herein, an amorphous Ni−Mo−B−O bifunctional electrocatalyst was synthesized through a facile electrodeposition method and employed as a cathode for HER to produce H2 and as an anode for the conversion of hydroxymethylfurfural (HMF) to furandicarboxylic acid (FDCA). Besides leading to the formation of amorphous structures, the introduction of Mo and B can increase the electron density and optimize the electronic structure of the electrocatalyst, thus substantially increasing the catalytic activity of the catalyst. After continuous reaction at a constant potential of 0.58 V vs. Hg/HgO for 8 hours, the conversion of HMF reached 98.86 %, and the selectivity of the target product FDCA was as high as 92.97 %. Finally, a two‐electrolyzer system was constructed using the amorphous Ni−Mo−B−O as both cathode and anode to achieve simultaneous H2 production in the cathode chamber and FDCA production in the anode chamber at a low voltage. This work presents a promising strategy for the design and synthesis of high‐performance non‐noble metal electrocatalysts for efficient and cost‐effective H2 production.