We　demonstrate　a　Q-switched　Ytterbium-doped　double-cladding　fiber　laser　based　on　single-walled　carbon　nanotubes　as　saturable　absorbers.　The　pure　single-walled　carbon　nanotubes　were　directly　deposited　on　the　one　end　of　the　Ytterbium-doped　double-cladding　fiber　by　optically　driven　deposition　method.　A　linear-cavity　was　employed　and　a　1.5m　long　Ytterbium-doped　double-cladding　fiber　played　as　the　gain　fiber.　The　Ytterbium-doped　double-cladding　fiber　was　pumped　by　a　976-nm　fiber　coupled　diode　laser.　The　maximum　output　power　of　1.3W　was　obtained　at　the　wavelength　of　1070nm.　The　pulse-repetition　rates　were　tuned　from　9.1　KHz　to　60　KHz　when　the　pump　powers　were　changed　from　1.85W　to　10W　and　the　shortest　pulse　duration　was　around　600ns.