In　this　study,　underwater　explosion　tests　with　2.5　g　trinitrotoluene　explosive　under　different　fixed　plates　with　prefabricated　holes　were　conducted.　The　experimental　results　showed　that　the　air　inflow　from　the　prefabricated　hole　caused　the　bubble　to　collapse　earlier　with　an　increase　in　the　hole　diameter.　In　addition,　the　deformation　mode　of　the　thin　plate　transitioned　from　＂convex＂　to　＂concave＂　(up　to　down).　Next,　the　coupled　Eulerian-Lagrangian　method　was　used　to　perform　the　corresponding　numerical　simulation.　The　accuracy　of　the　numerical　simulation　method　was　verified　through　a　comparison　with　the　experimental　data.　In　addition,　a　series　of　numerical　simulations　were　conducted　with　different　prefabricated-hole　diameters,　blast　distances,　and　prefabricated-hole　shapes.　The　results　showed　that　the　bubble-pulsating　water　jet　substantially　influenced　the　deformation　of　the　thin　plate　when　the　diameter　of　the　prefabricated　hole　was　within　the　theoretical　maximum　bubble　radius.　When　the　blast　distance　was　within　the　theoretical　maximum　bubble　radius,　the　thin　plate　was　subjected　to　only　a　single　bubble　pulsation　owing　to　the　air　inflow　from　the　prefabricated　hole.