A kind of hydrofoil, which is especially for use by helical vertical axis turbine for power generation from marine current, has been optimized by means of traditional genetic algorithms combined with hierarchical fair competition model. Bezier curve is used to parameterize the hydrofoils and numerical analysis is also introduced to evaluate hydrodynamic performance. Special fitness function as well as modified total lift–drag ratio is discussed in detail. Turbine performance tests and flow visualization experiments by PIV are conducted in order to draw a comparison between the optimized and two other competitive hydrofoils. The experimental results demonstrate that the optimized is more suitable to marine condition and beneficial to turbine efficiency improvement, and can be expected to act as a prospective hydrofoil for helical vertical axis turbine.