Yb:KGW laser material is well suited to build diode-pumped pulse lasers in watt region because of its broad gain bandwidth of 24 nm, large emission cross section of 2.8×10- 20 cm2 and good thermal conductivity of 3.3 W/(m·K). A passively Q- switched Yb:KGW laser is obtained using a transmission- type topological insulator Bi2Se3 as a saturable absorber. The achieved maximum pulse energy is 4.7 μJ and the peak power is 3.13 W for a pulse duration of 1.5 μs.