The　tuning　characteristics　of　widely　tunable　wavelength　vertical-cavity　surface-emitting　lasers　(VCSELs)　have　been　investigated　based　on　transfer　matrix　model　and　finite-element　structure-electric　coupled-field　analysis　model　and　experiment,　in　which　the　electrostatic　tuning　of　wavelength　and　microelectronic　mechanical　system　(MEMS)　cantilever　of　the　tunable　VCSELs　with　central　wavelength　980　nm　were　designed.　The　analysis　shows　that　the　characteristics　of　wavelength　tuning　of　VCSELs　will　be　affected　by　the　maximal　displacement　of　cantilever　and　the　structure　of　wavelength　resonator.　The　tuning　range　can　be　improved　based　on　the　optimization　of　sacrificial　layer　for　a　given　geometry　of　cantilever　and　active　region　of　the　device.　In　this　paper,　the　structure　of　tunable　VCSEL　is　designed.　Further　numerical　simulations　show　that　a　continuous　tuning　range　up　to　32　run　is　obtainable,　tuning　efficiency　is　0.12,　and　the　whole　tuning　range　of　wavelength　lies　within　the　high　gain　region　of　the　InGaAs　quantum　wells　with　GaAs　barrier.