Water-soluble　conjugated　polymers　(WSCPs),　distinguished　by　their　unique　optoelectronic　properties　and　water　solubility,　have　found　versatile　applications.　Despite　the　fact　that　pyrazine　and　its　fused　ring　serve　as　pivotal　building　blocks　in　high-performance　conjugated　polymers,　the　exploration　of　WSCPs　incorporating　a　pyrazine　ring　in　the　backbone　has　been　limited　due　to　synthetic　challenges.　Herein,　we　developed　a　new　synthetic　strategy　with　synchronized　pyrazine　construction　and　polymerization　that　can　transform　vinyl　azides　into　pyrazine　cores　under　metal-free　and　open-to-air　conditions.　Employing　this　approach,　we　designed　and　prepared　a　series　of　novel　pyrazine-based　WSCPs　with　good　water　solubility　and　fluorescence　properties.　Remarkably,　the　photoluminescence　intensity　of　WSCPs　with　free　carboxyl　groups　surpassed　that　of　conjugated　polymers　featuring　ester　groups.　Single　crystal　X-ray　diffraction　analysis　and　DFT　calculations　indicated　that　this　enhancement　could　be　attributed　to　the　presence　of　pyrazine　rings　and　carboxyl　groups　in　the　polymer　backbone,　facilitating　the　formation　of　intermolecular　hydrogen　bonds.　These　interactions　could　effectively　restrict　vibrational　relaxation　and　minimize　the　loss　of　energy　via　nonradiative　decay　pathways,　ultimately　resulting　in　higher　emission　intensity.　©　2024　American　Chemical　Society.