The　nonlinear　flexural　vibration　properties　of　double　layered　viscoelastic　nanoplates　are　investigated　based　on　nonlocal　continuum　theory.　The　von　Kaman　strain-displacement　relation　is　employed　to　model　the　geometrical　nonlinearity.　Based　on　the　classical　plate　theory,　the　formulations　are　derived　by　the　Hamilton＇s　principle　in　conjunction　with　Eringen＇s　nonlocal　elasticity　theory,　and　are　further　discretized　by　the　Galerkin＇s　method.　The　coordinate　transformation　is　adopted　to　obtain　the　nonlinear　governing　equations　of　motion　in　the　modal　coordinate　system.　On　the　basis　of　these　equations,　the　frequency　responses　of　double　layered　nanoplates　with　simply　supported　and　clamped　boundary　conditions　are　derived　by　the　method　of　multiple　scales.　The　influences　of　small　scale　and　other　structural　parameters　(e.g.　the　aspect　ratio　of　the　plate,　van　der　Walls　(vdW)　interaction　and　the　viscidity　of　the　plate)　on　the　nonlinear　vibration　characteristics　are　discussed.　From　the　result,　the　vdW　interaction　has　obvious　effects　on　the　nonlinear　frequency　corresponding　to　the　second　nonlinear　normal　mode　(NNM).　The　nonexistence　of　the　internal　resonance　is　also　induced　from　the　vdW　forces　between　the　plates.　The　influence　of　the　elastic　matrix　is　also　discussed.　The　hardening　nonlinearity　is　observed　for　the　primary　resonance.　Additionally,　some　interesting　phenomena　different　from　the　linear　vibraticin　are　observed.　(C)　2014　Elsevier　B.V.　All　rights　reserved.