PurposeIn　this　study,　for　the　first　time,　a　nonlinear　energy　sink　(NES)　is　used　to　suppress　the　nonlinear　dynamic　responses　of　graphene　platelet-reinforced　composite　(GPLRC)　lattice　sandwich　plates　under　blast　loads　in　thermal　environments.MethodsThe　face　sheets　and　lattice　core　trusses　of　the　lattice　sandwich　plates　are　reinforced　with　graphene　platelets.　The　effective　elastic　modulus　of　the　GPLRC　is　determined　using　the　Halpin-Tsai　micromechanical　model,　and　its　Poisson＇s　ratio,　mass　density,　and　coefficient　of　thermal　expansion　are　calculated　by　the　rule　of　mixture.　The　Kirchhoff　plate　and　the　first-order　shear　deformation　theories　are　used　to　model　the　face　sheets　and　the　lattice　core　layer　of　the　structure,　respectively.　The　nonlinear　strain-displacement　relationship　is　derived　using　the　von　Karman　large　deformation　theory.　The　motion　equations　of　simply　supported　GPLRC　lattice　sandwich　plates　with　an　NES　under　supersonic　flow　are　derived　using　Lagrange＇s　equation　and　the　assumed　mode　method.　The　nonlinear　dynamic　responses　of　a　GPLRC　lattice　sandwich　plate　system　coupled　with　an　NES　are　solved　using　Newmark　direct　integration　combined　with　the　Newton-Raphson　iteration　technique.Results　and　ConclusionsA　detailed　study　on　the　effects　of　an　NES　on　the　suppression　of　the　dynamic　behaviors　of　GPLRC　lattice　sandwich　plates　is　carried　out.　The　results　indicate　that　an　NES　can　significantly　reduce　the　amplitude　of　the　nonlinear　dynamic　response　of　GPLRC　lattice　sandwich　plates.By　optimizing　mass,　damping,　and　nonlinear　stiffness　values,　the　most　effective　suppression　of　the　structure　can　be　achieved　through　the　use　of　an　NES.