The　free　vibration　of　cracked　functionally　graded　material　(FGM)　plate　in　fluid　is　investigated　in　this　paper.　The　material　components　are　supposed　following　the　power　law　and　formulated　by　the　Voigt　model.　The　Mindlin　plate　theory　(MPT)　including　the　shear　deformation　effect　is　established　and　the　physical　neutral　plane　is　adopted　to　simplify　the　derivation　due　to　the　in-plane　displacements　of　this　plane　assumed　as　zero.　A　massless　linear　rotational　spring　model　(LRSM)　is　established　to　simulate　the　through-width　surface　crack.　The　hydrodynamic　pressure　at　the　fluid-plate　interface　is　derived　by　the　potential　flow　theory,　and　is　regarded　as　the　added　mass　of　cracked　FGM　plate　during　the　analyses　of　fluid-plate　coupled　vibration.　The　derivation　and　discretization　of　vibrational　equations　for　cracked　FGM　plates　in　fluid　are　respectively　achieved　though　the　Hamilton＇s　principle　and　differential　quadrature　(DQ)　method.　The　frequencies　and　mode　shapes　are　iteratively　calculated　with　these　values　of　the　vacuum　case.　The　influences　of　immersed　depth,　fluid　density,　gradient　index,　crack　depth,　crack　location,　length-to-width　ratio,　length-to-thickness　ratio,　and　boundaries　on　vibration　characteristics　are　conducted　in　the　section　of　numerical　results.　The　present　vibration　analyses　of　cracked　structures　can　be　applicable　to　avoid　structural　resonance　and　failure.