Based on the large eddy simulation method, the simulation model of annular swirling viscous jet was established and the breakup process and surface wave of annular swirling viscous jet were studied. The results show that the difference of velocity distribution between gas and liquid will lead to cavity in the liquid film. The cavity becomes larger and merges with others, and then the liquid film breaks into liquid ligaments. The liquid ligaments with a lengthtodiameter ratio of 3-15 account for 83.2% of the total. Under the leading role of inertia force, the split liquid ligaments show a necking phenomenon and break into droplets. Under the action of aerodynamics and turbulent pulsation, the surface wave forms on the surface of liquid sheet. When the axial velocity increases in the range of 100-150 m/s, the wavelength growth rate of axial surface wave obviously increases. With the increase of circumferential velocity, the wavelength growth rate of circumferential surface wave gradually increases.