The drag-type vertical axis wind turbines (VAWTs) have advantages of simple structure, self-starting at low wind speed and low cost, but they show low wind energy conversion efficiencies. A novel vertical axis wind turbine is proposed aiming to improve the disadvantage of the traditional wind turbines based on bionic principle in this paper. The structure of the novel vertical axis wind rotor is designed by combining traditional Savonius wind rotor structure and fish's ridge structure. Aerodynamic performance of the novel wind rotor and a traditional Savonius wind rotor are numerically explored and predicted by numerical simulation method for their non-linear two-dimensional unsteady flows. Performance comparison of the two wind rotors is also carried out. The results show that the novel wind rotor has better performance for torque and power coefficient on lower tip speed ratio (TSR) conditions than traditional Savonius rotor. Based on the simulation analysis of the two different types of wind rotors, we present the approach of changing and reconstructing different curvatures to obtain higher efficiency.