Abstract: In order to improve the starting characteristics of SB-VAWT, a wind-cup structure is installed inside the wind turbine. Through static torque wind tunnel test and PIV visualization test, the influence of wind-cup structure on the starting characteristics of double-blade SB-VAWT is studied. The results show that the wind-cup structure has a significant influence on the inner flow of the SB-VAWT. At some azimuth angles, the flow separation phenomenon at the tail of SB-VAWT lift blade is improved by the wind-cup structure, and the vortex is weakened, reducing the energy loss. In a rotation period, the existence of the wind-cup structure also produces the torque acting on the rotor axis, so the static starting moment of the vertical axis wind turbine with the wind-cup structure is higher than the static starting moment of SB-VAWT.