Construction　of　local　donor–acceptor　architecture　is　one　of　the　valid　means　for　facilitating　the　intramolecular　charge　transfer　in　organic　semiconductors.　To　further　accelerate　the　interface　charge　transfer,　a　ternary　acceptor–donor–acceptor　(A1-D-A2)　molecular　junction　is　established　via　gradient　nitrogen　substituting　into　the　polymer　skeleton.　Accordingly,　the　exciton　splitting　and　interface　charge　transfer　could　be　promptly　liberated　because　of　the　strong　attracting　ability　of　the　two　different　electron　acceptors.　Both　DFT　calculations　and　photoluminescence　spectra　elucidate　the　swift　charge　transfer　at　the　donor-acceptor　interface.　Consequently,　the　optimum　polymer,　N3-CP,　undergoes　a　remarkable　photocatalytic　property　in　terms　of　hydrogen　production　with　AQY405　nm=26.6　%　by　the　rational　design　of　asymmetric　molecular　junctions　on　organic　semiconductors.　©　2020　Wiley-VCH　GmbH