We　experimentally　demonstrate　wavelength-tunable　self-mode-locking　(SML)　operation　generated　in　an　optically　pumped　semiconductor　disk　laser　(OP-SDL)　with　a　straight　cavity.　The　operation　is　achieved　by　insetting　an　etalon　into　the　cavity,　and　wavelength　tuning　range　of　11　nm　can　be　achieved　by　adjusting　the　angle　of　etalon.　After　aligning　the　cavity　carefully,　stable　self-mode-locking　is　obtained　when　the　pump　power　was　beyond　5　W,　and　the　pulse　period　of　0.99　ns　agrees　well　with　the　round-trip　time　determined　by　the　optical　cavity　length　of　148　mm.　Meanwhile,　the　RF　spectrum　reveals　a　clean　peak　at　the　fundamental　repetition　rate　of　1.01　GHz　and　the　signal-to-noise　ratio　of　the　RF　spectrum　reaches　60　dB　during　the　whole　tuning　process,　indicating　the　stability　of　the　pulse　was　quite　excellent.　Finally,　we　obtained　a　wavelength-tunable　SML　optically　pumped　semiconductor　disk　laser.　The　experimental　results　prove　that　under　the　condition　of　adding　an　etalon　in　the　cavity,　the　OP-SDL　could　remain　a　stable　operation　in　a　wider　wavelength　tuning　range.　This　research　is　helpful　to　the　development　of　wavelength　tunable　self-mode-locking　optically　pumped　semiconductor　disk　lasers,　and　hopes　to　obtain　practical　applications　in　related　fields.　©　2022　SPIE.