In　a　coastal　ecological　project　aimed　at　wave　attenuation　through　mangroves,　incorporating　oyster　reefs　as　a　complementary　component　to　establish　an　＇oyster　reefs　+　mangrove＇　wave　attenuation　system　could　enhance　the　survival　probability　of　mangroves,　as　well　as　improve　the　overall　effectiveness　of　wave　attenuation.　This　study　investigates　and　proposes　an　innovative　wave　attenuation　system　consisting　of　oyster　reefs　and　mangroves　with　various　configurations.　Laboratory　experiments　were　conducted　in　a　wave　flume　using　artificial　models　of　mangroves　and　oyster　reefs　to　examine　the　impact　of　the　system　on　wave　attenuation,　thereby　providing　a　scientific　foundation　for　coastal　ecological　restoration　projects.　The　findings　demonstrate　that　the　wave　attenuation　coefficient　exhibited　a　positive　correlation　with　both　the　significant　wave　height　and　oyster　reef　height,　as　well　as　with　mangrove　density.　Conversely,　it　displayed　a　negative　association　with　water　depth　and　period.　Notably,　oyster　reefs　substantially　affected　the　wave　attenuation.　When　three　layers　of　oyster　reefs　are　integrated　with　staggered　dense　mangroves,　the　system　demonstrates　optimal　wave　attenuation,　with　coefficients　ranging　from　0.38　to　0.42.　The　incorporation　of　oyster　reefs　within　mangroves　significantly　enhances　the　capacity　of　wave　attenuation,　resulting　in　an　increase　of　up　to　0.26　in　the　wave　attenuation　coefficient.　Moreover,　although　the　combined　wave　attenuation　coefficient　of　the　individual　mangroves　and　oyster　reefs　was　higher　than　that　of　the　system,　the　system’s　overall　wave　attenuation　surpassed　that　of　either　component.　A　theoretical　equation　has　been　formulated　to　quantify　wave　attenuation　in　the　oyster　reefs-mangrove　system,　aiming　to　provide　practical　guidance　for　coastal　restoration　projects.　Maximizing　the　height　of　oyster　reefs　in　areas　with　low　water　depth　and　pairing　them　with　staggered　dense　mangroves　is　recommended　to　reduce　wave　energy　in　coastal　restoration　projects.　The　most　effective　wave　reduction　strategy　for　areas　with　high　water　depth　is　a　combination　of　tall　oyster　reefs　and　staggered　or　in-line　clusters　of　dense　mangroves.　©　The　Author(s),　under　exclusive　licence　to　Springer-Verlag　GmbH　Germany,　part　of　Springer　Nature　2025.