The　aim　of this　paper is　to investigate　the　stability　of　a　simply　supported　laminated　composite　piezoelectric　rectangular　plate　under　combined　excitations.　Analysis　of　the　amplitude　and　phase　modulation　equations　with　the　associated　nonlinear　interaction　coefficients,　as　provided　by　the　multiple　scale　analyses　of　various　1:1　internal　resonance　conditions　and　primary　resonance　case,　where　ω　2≅　ω　1　and　Ω　3≅　ω　1　is　considered.　The　method　of　multiple　time　scale　is　applied　to　solve　the　non-linear　differential　equations　describing　the　system　up　to　the　second-order　approximation.　All　possible　resonance　cases　at　this　approximation　order　are　extracted.　The　stable/unstable　periodic　solutions　are　determined　and　are　presented　through　frequency　response　plots.　The　analytical　results　are　verified　by　comparing　them　with　those　of　numerical　integration　of　the　modal　equations.　The　influence　of　different　parameters　on　the　dynamic　behavior　of　the　composite　laminated　piezoelectric　rectangular　plate　is　studied.　Variation　of　the　some　parameters　leads　to　multi-valued　amplitudes　and　hence　to　jump　phenomena.　A　comparison　with　the　available　published　work　is　reported.　©　2014,　Springer-Verlag　Berlin　Heidelberg.