The　acoustic　model　of　three-layer　bonding　structure　in　water　when　oblique　incidence　is　established,　the　acoustic　impedance　method　and　spring　model　are　used　to　derive　the　representation　of　transmission　coefficient　of　three-layer　bonding　structure　when　oblique　incidence;　and　the　numerical　simulation　is　done　to　analyze　the　influence　of　the　incidence　angle,　the　adhesive　thickness,　the　steel　plate　thickness,　the　substrate　materials　on　the　transmission　coefficient;　at　the　same　time,　the　influence　of　the　change　in　stiffness　coefficient　on　the　transmission　coefficient　of　the　weak　bonding　structure　is　studied.　To　verify　the　theoretical　derivation,　the　experiment　on　the　three-layer　bonding　structure　(steel-epoxy-steel)　in　water　when　oblique　incidence　is　done,　the　test　results　are　in　good　agreement　with　the　theoretical　results.　The　results　show　that,　the　changes　in　incidence　angle　and　other　parameters　will　cause　the　change　of　resonant　frequency　points　or　the　peak　of　transmission　coefficient;　the　bonding　structure　is　weak　bonding　structure　when　the　stiffness　coefficient　is　small,　there　is　more　than　one　peak　of　transmission　coefficient,　and　the　phenomenon　of　more　than　one　peak　is　disappeared　when　good　adhesion.　©　2013　Journal　of　Mechanical　Engineering.