Although　epoxy　resin　(EP)　offers　excellent　performance　for　diverse　applications,　its　high　flammability　and　toxic　smoke　emission　pose　significant　safety　and　environmental　concerns.　Traditional　flame　retardants　often　destroy　mechanical　properties　while　failing　to　address　smoke　suppression.　This　paper　reports　a　phytic　acid-melamine　salt　(PA@MEL)　flame　retardant　synthesized　using　bio-based　phytic　acid　and　melamine　via　a　green　water-soluble　process.　In　this　study,　PA@MEL　was　developed　as　a　dual-functional　additive　for　use　as　both　a　flame　retardant　and　room-temperature　co-curing　agent　for　EP,　achieving　simultaneous　flame　retardancy,　smoke　suppression,　and　mechanical　property　preservation　through　an　optimized　composition.　The　results　of　the　flame　retardant　tests　showed　that　EP/PA@MEL-15%　could　pass　the　V-0　level　of　the　vertical　burning　test　with　an　LOI　of　28.9%.　With　15　mass%　PA@MEL　loading,　the　composite　significantly　reduced　the　peak　heat　and　smoke　release　by　60.6%　and　54.3%,　respectively,　and　CO2　and　CO　production　rates　by　45.9%　and　43.0%,　respectively.　In　addition,　mechanical　tests　of　the　EP/PA@MEL　composites　demonstrate　that　PA@MEL　has　excellent　mechanical　properties　in　EP.　This　work　establishes　a　sustainable　strategy　for　manufacturing　high-performance　epoxy　composites,　overcoming　the　traditional　trade-off　between　flame　retardancy　and　mechanical　properties.　The　room-temperature　curing　capability　and　bio-based　composition　of　PA@MEL　make　it　particularly　attractive　for　industrial　applications.