This　paper　is　devoted　to　consider　the　existence　and　bifurcation　of　subharmonic　solutions　of　two　types　of　2n-dimensional　nonlinear　systems　with　time-dependent　perturbations.　When　the　unperturbed　system　is　a　Hamiltonian　system,　we　obtain　the　extended　Melnikov　function　by　means　of　performing　the　curvilinear　coordinate　frame　and　constructing　a　Poincare　map.　Then　some　conditions　of　the　bifurcation　of　subharmonic　solutions　are　obtained.　The　results　obtained　in　this　paper　contain　and　improve　the　existing　results　for　n=2,3.　When　the　unperturbed　system　contains　an　isolated　invariant　torus,　we　investigate　the　bifurcation　of　subharmonic　solutions　by　analyzing　the　Poincare　map.　We　apply　the　extended　Melnikov　method　to　study　the　bifurcation　and　number　of　subharmonic　solutions　of　the　ice-covered　suspension　system.　The　maximum　number　of　subharmonic　solutions　of　this　system　is　2,　and　the　relative　parameter　control　condition　is　obtained.