Although　the　stability　of　the　sandwich　structures　under　in-plane　excitation　has　been　reported,　few　of　them　focus　on　the　functionally　graded　materials　(FGM)　sandwich　doubly　curved　shallow　shells.　Moreover,　for　the　study　of　static　bifurcation,　stability　and　dynamic　stability　analysis,　it　is　common　to　ignore　the　effect　of　thickness　tension　or　compression.　The　purpose　of　this　paper　is　to　explore　the　bifurcation　and　stability　of　the　FGM　sandwich　doubly　curved　shallow　shell　which　is　subjected　to　the　in-plane　excitation　in　thermal　environment.　By　introducing　the　secant　function　to　the　transverse　displacement,　a　new　displacement　field　based　on　the　Reddy＇s　third　order　shear　deformation　theory　is　derived.　It　is　assumed　that　the　material　properties　of　sandwich　doubly　curved　shallow　shell　are　temperature　dependent.　The　distribution　of　component　materials　in　FGM　layer　obeys　the　rule　of　power　law　in　the　radial　direction.　Considering　the　geometric　nonlinear,　using　an　energy　approach　and　the　Galerkin＇s　method,　a　two-degree-of-freedom　non-autonomous　nonlinear　dynamic　equation　with　parametric　excitation　is　derived.　The　threshold　of　the　bifurcation　and　the　stability　of　the　structure　are　investigated.　The　instability　regions　are　plotted　by　dynamic　load　factor　against　excitation　frequency　in　alpha(1)　-　Omega　plane.