In order to improve the starting performance and wind energy utilization of the existing vertical axis wind turbine,a passive variable pitch structure based on gear linkage structure was proposed,and the feasibility of the variable pitch mechanism was verified by the kinematics simulation software ADAMS.Then the fluid solver Fluent was developed again,a set of program was developed to effectively solve the interaction between passive variable pitch vertical axis wing turbine and fluid flow,and the influence of different variable pitch amplitude on the energy capture performance of wind turbine was analyzed at 6 m/s wind speed.The results show that the proposed passive pitch mechanism can improve the start-up performance of the wind turbine,and the wind energy utilization rate of the wind turbine can reach 17.633% under the amplitude of ±25°.