Multi-pulse　chaotic　dynamics　of　a　simply　supported　functionally　graded　materials　(FGMs)　rectangular　plate　is　investigated　in　this　paper.　The　FGMs　rectangular　plate　is　subjected　to　the　transversal　and　in-plane　excitations.　The　properties　of　material　are　graded　in　the　direction　of　thickness.　Based　on　Reddy＇s　third-order　shear　deformation　plate　theory,　the　nonlinear　governing　equations　of　motion　for　the　FGMs　plate　are　derived　by　using　the　Hamilton＇s　principle.　The　four-dimensional　averaged　equation　under　the　case　of　1:　2　internal　resonance,　primary　parametric　resonance　and　1/2-subharmonic　resonance　is　obtained　by　directly　using　the　asymptotic　perturbation　method　and　Galerkin　approach　to　the　partial　differential　governing　equation　of　motion　for　the　FGMs　rectangular　plate.　The　system　is　transformed　to　the　averaged　equation.　From　the　averaged　equation,　the　theory　of　normal　form　is　used　to　find　the　explicit　formulas　of　normal　form.　Based　on　normal　form　obtained,　the　extended　Melnikov　method　is　utilized　to　analyze　the　multi-pulse　global　bifurcations　and　chaotic　dynamics　for　the　FGMs　rectangular　plate.　The　analysis　of　global　dynamics　indicates　that　there　exist　the　multi-pulse　jumping　orbits　in　the　perturbed　phase　space　of　the　averaged　equation.　From　the　averaged　equations　obtained,　the　chaotic　motions　and　the　Shilnikov　type　multi-pulse　orbits　of　the　FGMs　rectangular　plate　are　found　by　using　numerical　simulation.　The　results　obtained　above　mean　the　existence　of　the　chaos　for　the　Smale　horseshoe　sense　for　the　simply　supported　FGMs　rectangular　plate.