We　demonstrated　a　wavelength　tunable　mode-locked　optically　pumped　semiconductor　disk　laser　(OP-SDL)　based　on　a　SESAM.　The　wavelength　tuning　is　achieved　by　incorporating　an　uncoated,　100　μm　thick,　fused　silica　etalon　into　the　cavity　of　the　laser,　and　the　central　wavelength　of　the　pulse　train　varied　from　972　nm　to　977　nm.　The　average　power　of　the　mode-locked　states　measured　at　different　wavelengths　was　about　80mW,　meanwhile,　the　repetition　rate　was　1.2　GHz　in　the　tuning　process,　and　the　signal-to-noise　ratio　of　the　radio　frequency　spectrum　signal　exceeds　50　dB,　which　illustrates　that　the　laser　can　maintain　a　stable　mode-locked　state　even　the　central　wavelength　varies　greatly.　In　addition,　we　calculated　the　influence　of　etalon＇s　related　parameters　on　its　transmittance.　This　research　contributes　to　the　development　of　wavelength-tunable　mode-locked　OP-SDLs　and　to　gain　practical　applications　in　related　fields.　©　2022　SPIE.