Semiconductor　disk　lasers　can　produce　high　output　power　and　good　beam　quality　simultaneously.　The　high　intracavity　circulating　power　of　about　hundreds　of　watts,　along　with　the　flexibility　of　tailorable　emitting　wavelengths,　make　it　an　attractive　light　source　for　obtaining　ultraviolet　(UV)　radiation　from　near-infrared　lasers　through　nonlinear　frequency　conversion.　This　work　reports　a　frequency　tripled　327　nm　semiconductor　disk　laser　with　record　output　power　and　wavelength　tuning　range　by　using　a　type-I　phase-matched　LiB3O5　(LBO)　crystal　and　a　type-I　phase-matched　β-BaB2O4　(BBO)　crystal　as　the　frequency-doubling　and　-tripling　crystals　respectively.　Thanks　to　the　obviously　larger　nonlinear　coefficient　of　the　type-I　phase-matched　BBO　compared　to　the　commonly　used　type-II　phase-matched　LBO,　as　well　as　the　small　spot　size　specifically　designed　at　the　crystal　location,　the　maximum　output　power　of　UV　lasers　reaches　538　mW,　corresponding　to　an　optical-to-optical　conversion　efficiency　from　pump　to　UV　laser　of　about　1.14%.　A　wavelength　tuning　range　of　about　8.6　nm　and　good　power　stability　with　a　standard　deviation　of　about　0.94　are　also　achieved.　©　2024　Optica　Publishing　Group　under　the　terms　of　the　Optica　Open　Access　Publishing　Agreement.