A full-scale wind tunnel tests have been conducted to investigate the rotor hub drag characteristics of a coaxial rigid rotor through a rotor hub test rigin China Aerodynamics Research and Development CenterFL-14 wind tunnel. The test modelsare typical coaxial rigid rotor hub models, including the upper and lower hub fairing models and four intermediate shaft fairing models. There are four interchangeable mid-shaft fairings designed, i.e. , three optimized fairings based on airfoil shape , and a bare shaft for reference. Multiple fairing geometries are tested at different rotational speeds, wind velocity and different attitude angle in wind tunnel to obtain basic aerodynamic loads. The effect of blade stub on drag of rotor hub is also analyzed. Drag characteristics between three fairings and bare shaft are compared, and the influence law of coaxial rotors hub drag is obtained. The experimental results show that the best fairing configurationreduces the drag from a bare hub by 37%.