Poly(heptazine　imide)　(PHI),　one　of　the　attractive　allotropes　of　polymeric　carbon　nitride,　has　recently　received　extensive　attention　in　photocatalysis　due　to　its　extended　conjugation　for　fast　separation　and　transfer　of　the　charges.　However,　pristine　PHI　bears　an　intrinsic　optical　absorption　band　edge　at　460　nm,　which　largely　restrains　the　visible　light　utilization.　Herein,　the　narrow-bandgap　PHI　(N-PHI)　with　an　ordered-distorted　interface　was　fabricated　from　polycondensation　of　the　mixture　of　NaSCN,　cyanuric　chloride,　and　LiCl.　Results　revealed　that　the　enhanced　optical　absorption　and　the　promoted　separation　and　transfer　of　the　charge　carriers　at　the　interface　greatly　improved　the　photocatalytic　performance,　which　endowed　N-PHI　with　an　apparent　quantum　yield　of　20　%　for　hydrogen　production　at　450　nm.　©　2022　Wiley-VCH　GmbH.