This study analyzed the influence of aerodynamic damping on frequency domain response of floating wind turbine. The 5 megawatt (MW) floating wind turbine model built by the National Renewable Energy Laboratory (NREL) of America was selected as an example. The aerodynamic damping matrix of the motion for the rigid body was established according to aerodynamic damping calculation method. Hydrodynamic coefficients were computed based on the three-dimensional potential flow theory, and the stiffness of mooring system was also taken into account as linear spring. Motion equations of the wind turbine with or without consideration of aerodynamic damping were then established and solved in frequency domain, respectively. The influence of aerodynamic damping on the motion of the floating wind turbine was examined in frequency domain through the response amplitude operators (RAOs) by solving the equations, and the response spectrum was derived from RAOs and JONSWAP wave spectrum. The results show that aerodynamic damping can effectively reduce the peak values of the surge and pitch RAOs under operating condition, and decrease the amplitude and zero-order moment of the corresponding response spectrum to a certain degree.