In　general,　seawater-immersed　wounds　are　associated　with　tissue　necrosis,　infection,　prolonged　healing　period,　and　high　mortality　because　of　high　salinity,　hyperosmosis,　and　the　presence　of　various　pathogenic　bacteria　in　seawater.　However,　current　wound　dressings　can　hardly　achieve　strong　and　stable　wet　ad-hesion　and　antibacterial　properties,　thus　limiting　their　application　to　seawater-immersed　wounds.　Here　a　multifunctional　hydrogel　(OD/EPL@Fe)　comprising　catechol-modified　oxidized　hyaluronic　acid　(OD),　epsilon-poly-L-lysine　(EPL),　and　Fe3　+　was　prepared　primarily　through　Schiff-base　reaction,　metal　chelation,　cation-x,　and　electrostatic　interaction.　The　hydrogel　with　high　wet　adhesion　(about　78　kPa)　was　achieved　by　combining　the　mussel-inspired　strategy,　dehydration　effect,　and　cohesion　enhancement,　which　is　higher　than　that　of　commercial　fibrin　glues　and　cyanoacrylate　glues.　Meanwhile,　the　hydrogel　can　elimi-nate　Marine　bacteria　(　V.　vulnificus　and　P.　aeruginosa)　and　inhibit　their　biofilm　formation.　In　addition,　the　hydrogel　demonstrated　injectability,　self-healing,　reactive　oxygen　species　scavenging　activity,　photother-mal　effect,　seawater　isolation,　on-demand　removal,　and　hemostatic　properties.　In　vivo　results　showed　that　the　hydrogel　had　good　adhesion　to　dynamic　wounds　in　a　rat　neck　full-thickness　skin　wound　model.　In　particular,　the　hydrogel　exhibited　antibacterial,　anti-inflammatory,　and　antioxidant　properties　in　a　rat　seawater-immersed　infected　wound　model　and　accelerated　the　reconstruction　of　skin　structure　and　func-tions.　The　results　demonstrated　that　the　OD/EPL@Fe　would　be　a　potential　wound　dressing　for　seawater-immersed　wound　healing.Statement　of　Significance　A　multifunctional　OD/EPL@Fe　hydrogel　has　been　prepared　for　the　treatment　of　seawater-immersed　wounds.　The　hydrogel　with　high　wet　adhesion　was　achieved　by　combining　the　mussel-inspired　strategy,　dehydration　effect,　and　cohesion　enhancement.　The　results　revealed　that　the　wet　adhesion　value　of　hy-drogel　was　about　eight　times　greater　than　commercial　fibrin　glues　and　1.5　times　greater　than　commercial　cyanoacrylate　glues.　The　hydrogel　can　be　easily　removed　after　being　sprayed　with　deferoxamine　mesylate.　Notably,　the　inherent　antimicrobial　material　of　the　hydrogel　combined　with　the　photothermal　effect　can　eliminate　marine　bacteria　and　inhibit　their　biofilm　formation.　Moreover,　the　hydrogel　can　accelerate　the　healing　of　seawater-immersed　infected　wound　on　mice.(c)　2023　Acta　Materialia　Inc.　Published　by　Elsevier　Ltd.　All　rights　reserved.