Cu-based　bimetallic　catalysts　have　been　studied　in　the　electrocatalytic　nitrate　(NO3-)　reduction　reaction　(NO3-RR)　for　a　long　time.　However,　few　studies　have　focused　on　horizontal　comparison　of　CuNi,　CuCo,　and　CuFe　(abbreviated　as　CuM)　bimetallic　catalysts　in　electrocatalytic　NO3-RR　for　ammonia　synthesis.　Herein,　we　prepare　the　three　series　of　Cu-based　bimetallic　catalysts,　with　different　atom　ratios　of　Cu/M　(Cu/M　=　7/3,　5/5,　or　3/7)　and　ordered　mesoporous　carbon　(OMC)　as　support　(denoted　as　CuM/OMC).　The　characterization　results　reveal　that　the　metallic　particles　of　Cu　and　M　components　possess　an　intimate　relationship　on　the　CuM/OMC　catalysts.　The　electrocatalytic　NO3-RR　performance　uncovers　that　the　optimal　NH3　yield　rates　of　CuM/OMC　catalysts　at　−0.8　V　(vs　reversible　hydrogen　electrode　(RHE))　follow　this　order:　Cu5Fe5/OMC　>　Cu5Co5/OMC　>　Cu7Ni3/OMC　>　Cu/OMC　>　Fe/OMC　>　Co/OMC　>　Ni/OMC　>　OMC.　The　bimetallic　CuM/OMC　catalysts　exhibit　higher　NH3　yield　rates　than　the　monometallic　catalysts.　This　is　attributed　to　strong　synergistic　effects　between　the　Cu　and　M　components.　We　expect　that　these　insights　can　stimulate　new　developments　of　bimetallic　catalysts　in　electrocatalysis.　©　2023　American　Chemical　Society.