The　incorporation　of　organic　molecules　in　the　framework　of　carbon　nitride　(CN)　polymers　by　co-polymerization　is　a　conventional　strategy　to　optimize　the　optoelectronic　properties　and　thus　improve　the　photoactivity　of　CN　polymers.　Herein,　we　report　π-deficient　pyridine　ring,　namely　2,　6-diaminopyridine,　as　organic　monomer　to　bind　into　the　conjugation　system　of　CN　polymers.　The　optimal　CN　polymer　has　presented　improved　efficiency　of　visible　light　absorption,　and　it　shows　enhanced　photocatalytic　activity　over　non-modified　CN　photocatalyst　in　the　H2　evolution　reaction　and　CO2　reduction　reaction　under　visible　light　illumination.　This　co-polymerized　photocatalyst　offers　opportunities　for　further　developments　of　advanced　photoredox　catalysis　using　sustainable　polymeric　semiconductors.　©　2021,　Springer　Nature　B.V.