A　Q-switched　Yb:KGW　solid-state　laser　using　topological　insulator　Bi2Se3　as　a　saturable　absorber　was　demonstrated　experimentally　for　the　first　time.　The　Bi2Se3　saturable　absorber　was　fabricated　in　a　film　on　a　highly　reflective　mirror.　By　inserting　this　into　a　Yb:KGW　laser,　the　Q-switched　operation　was　obtained.　The　highest　average　output　power　was　439.4　mW　and　the　corresponding　repetition　rate,　pulse　width　and　pulse　energy　were　166.7　kHz,　1.6　mu　s　and　2.64　mu　J,　respectively.　To　our　knowledge,　this　is　the　highest　output　power　among　topological　insulator-modulated　lasers　with　topological　insulator　absorbers.