The　dynamic　properties　of　a　simply　supported　at　four　edges　truss　core　sandwich　plate　with　tetrahedral　core　are　investigated　in　this　paper.　The　nonlinear　governing　equation　of　motion　for　the　truss　core　sandwich　plate　is　derived　by　using　the　Hamilton＇s　principle,　the　von　Karman　type　equation　for　the　geometric　nonlinearity　and　a　Zig-Zag　theory.　The　partial　differential　equation　is　reduced　to　a　single　degree　of　freedom　ordinary　differential　equation　by　applying　the　Galerkin＇s　approach.　The　two-dimensional　averaged　equation　is　derived　by　using　the　method　of　multiple　scales　and　the　frequency　response　equation　is　obtained.　The　influences　of　the　core　height,　the　strut　radius　and　the　inclination　angle　of　the　truss　core　on　the　first-order　linear　natural　frequency　and　the　nonlinear　frequency　response　of　the　sandwich　plate　are　studied.　The　changing　rules　and　its　mechanisms　of　the　natural　frequency　and　the　hardening　behavior　of　the　sandwich　plate　with　different　structural　parameters　are　presented.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.