Dual-wavelength　mode-locked　lasers　can　be　widely　used　in　optical　communication,　pump-probe　experiment,　nonlinear　frequency　conversion,　etc.　In　this　paper,　a　dual-wavelength　self-mode-locked　semiconductor　disk　laser　is　reported　for　the　first　time,　to　the　best　of　our　knowledge.　A　simple　linear　resonator　is　formed　by　using　a　high　reflectivity　distributed　Bragg　reflector　at　the　bottom　of　the　gain　chip,　and　an　external　output　mirror;　the　cavity　length　is　about　135　mm,　with　no　need　of　additional　inserted　elements.　Based　on　the　Kerr　effect　of　the　gain　medium　and　the　soft　aperture　formed　by　the　pump　spot　on　the　gain　chip,　along　with　the　fine　adjustment　of　cavity　length　and　pump　intensity,　the　mode-locking　process　can　be　started　from　the　free　running　and　the　stable　self-mode-locking　can　be　realized.　The　mode-locked　pulse　width　is　4.3　ps,　the　repetition　rate　is　1.1　GHz,　and　the　maximum　output　power　is　323.9　mW,　which　corresponds　to　a　peak　power　of　68　W.　After　the　laser　is　mode　locked,　a　readily　available　blade,　which　can　introduce　a　wavelength-dependent　loss　for　different　laser　modes,　resulting　in　a　lager　cavity　loss　for　a　longer-wavelength　mode　and　a　smaller　cavity　loss　for　a　shorter-wavelength　mode,　is　used　as　a　wavelength　tuning　element,　and　is　inserted　into　the　cavity　in　the　direction　perpendicular　to　the　optical　axis　of　the　resonator.　By　changing　the　depth　of　the　blade　inserted　into　the　cavity,　the　laser　wavelength　can　be　continuously　tuned　from　the　initial　oscillating　wavelength　(longer-wavelength)　to　a　shorter　wavelength,　a　stable　dual-wavelength　output　with　equal　intensity　can　be　obtained　at　a　specific　position,　and　the　stable　continuous-wave　mode-locking　can　be　maintained　simultaneously.　The　steady　dual-wavelengths　in　the　experiment　are　951　and　961　nm,　and　the　corresponding　output　power　is　32　mW.　The　above　dual-wavelength　outputs　have　good　coherence　since　they　are　stimulated　radiations　from　the　same　gain　chip.　Meanwhile,　they　have　relatively　high　peak　power　and　strictly　meet　the　coaxial　conditions,　and　these　are　all　advantages　for　the　difference　frequency　generation　(DFG).　The　frequency　of　the　DFG　in　the　experiment　is　approximately　3.3　THz,　which　can　be　widely　used　in　laser　radar,　remote　sensing,　homeland　security,　counter-terrorism,　atmospheric　and　environmental　monitoring　and　otherareas.　©　2022　Chinese　Physical　Society.