The　CO　reduction　reaction　(CORR)　for　the　production　of　high-value-added　multi-carbon　(C2+)　products　is　currently　being　actively　investigated,　where　searching　for　high-efficiency　catalysts　with　moderate　CO　intermediate　binding　strength　and　low　kinetic　barrier　for　C-C　coupling　poses　a　significant　challenge.　In　this　study,　we　employed　density　functional　theory　computations　to　design　four　synergistic　coupling　dual　sites　catalysts　for　CORR　to　C-2　products,　namely,　TM-P@melon,　by　co-doping　transition　metals　(TM　=　Mn,　Fe,　Co,　and　Ni)　and　phosphorus　(P)　into　the　polymeric　carbon　nitride　(i.e.,　melon-CN).　Mn-P@melon　and　Ni-P@melon　exhibit　higher　selectivity　toward　C2H5OH　and　C2H6,　respectively,　with　limiting　potentials　(C-C　coupling　kinetic　energy　barriers)　of　-0.43　V　(0.52　eV)　and　-0.17　V　(0.26　eV),　respectively.　The　introduction　of　TM　and　P　atoms　not　only　narrows　the　band　gap　of　melon-CN　but　also　favors　the　coupling　of　CO　and　*CHO,　providing　an　active　site　for　C-C　coupling,　thus　facilitating　the　catalytic　reaction.　Our　work　provides　rational　insights　for　the　design　of　stable,　low-cost,　and　efficient　CORR　dual　sites　catalysts　that　facilitate　the　sustainable　production　of　high-value　C-2　chemicals　and　fuels.