The　magnetic　surface　acoustic　wave　(MSAW)　devices　developed　in　recent　years　are　a　class　of　tunable　surface　acoustic　wave　devices　(such　as　filters,　tuners,　oscillators,　etc.)　which　are　important　parts　of　radar,　sonar,　TV,　computers　and　other　modern　communication　systems.　Giant　magnetostrictive　thin　films　(RGMFs)　have　high　energy,　large　magnetic　response,　and　high　elastic　modulus　as　well　as　the　function　that　sound　speed　can　alter　by　changing　the　magnetic　field.　Thus,　RGMFs　can　be　used　to　make　tunable　MSAW　devices.　The　vibration　characteristics　of　the　device　components　are　directly　related　to　the　service　status　and　the　life　of　devices.　In　order　to　optimize　and　design　RGMFs　materials,　in　this　paper,　SmFe2　samples　with　polyimide　(PI)　and　the　glass　as　substrates　are　studied,　and　the　natural　frequencies　of　SmFe2　monolayer　samples,　with　different　deposition　thickness,　are　derived　and　simulated　by　the　method　of　equivalent-section.　Furthermore,　vibration　data　(including　natural　frequencies　and　resonant　amplitudes)　of　the　SmFe2　samples　are　measured　by　the　Helmholtz　resonance　system.　The　results　show　that　the　differences　between　the　theoretical　predictions　and　the　experimental　results　are　within　8%.　Therefore,　the　equivalent-section　method　is　feasible　to　predict　the　natural　frequency　of　RGMFs　samples.　The　work　establishes　a　basis　for　the　development　of　MSAW　devices　using　RGMFs　materials.　©　2010　IEEE.