Marine　antifouling　coatings　that　rely　on　the　release　of　antifouling　agents　are　the　most　prevalent　and　effective　strategy　for　combating　fouling.　However,　the　environmental　concerns　arising　from　the　widespread　discharge　of　these　agents　into　marine　ecosystems　cannot　be　overlooked.　An　innovative　and　promising　alternative　involves　incorporating　antimicrobial　groups　into　polymers　to　create　coatings　endowed　with　intrinsic　antimicrobial　properties.　In　this　study,　we　reported　an　urushiol-based　benzoxazine　(URB)　monomer,　synthesized　from　natural　urushiol　and　antibacterial　rosin　amine.　The　URB　monomer　was　subsequently　polymerized　through　thermal　curing　ring-opening　polymerization,　resulting　in　the　formation　of　a　urushiol-based　benzoxazine　polymer　(URHP)　coating　with　inherent　antimicrobial　properties.　The　surface　of　the　URHP　coating　is　smooth,　flat,　and　non-permeable.　Contact　angle　and　surface　energy　measurements　confirm　that　the　URHP　coating　is　hydrophobic　with　low　surface　energy.　In　the　absence　of　antimicrobial　agent　release,　the　intrinsic　properties　of　the　URHP　coating　can　effectively　kill　or　repel　fouling　organisms.　Furthermore,　with　bare　glass　slides　serving　as　the　control　sample,　the　coating　demonstrates　outstanding　anti-adhesion　capabilities　against　four　types　of　bacteria　(E.　coli,　S.　aureus,　V.　alginolyticus,　and　Bacillus　sp.),　and　three　marine　microalgae　(N.　closterium,　P.　tricornutum,　and　D.　zhan-jiangensis),　proving　its　efficacy　in　preventing　fouling　organisms　from　settling　and　adhering　to　the　surface.　Thus,　the　combined　antibacterial　and　anti-adhesion　properties　endow　the　URHP　coating　with　superior　antifouling　performance.　This　non-release　antifouling　coating　represents　a　green　and　environmentally　sustainable　strategy　for　antifouling.　©　2025　by　the　authors.