Taking the 5 MW wind turbine with Barge platform as the research object, the aero-hydro-mooring dynamic model of the platform was established based on the blade element momentum theory, potential flow theory and finite element method. Considering the mooring failure in the worst case of wind and wave incident in the same direction, the floating wind turbine bears the maximum wind and wave load, and the mooring was most vulnerable to fatigue and impact loads. The dynamic response and mooring tension of the platform before and after mooring failure at different positions under high-speed turbulent wind and steady wind were compared and analyzed. The results show that the failure of the mooring system on the windward side has a significant influence on the response to multiple degrees of freedom. The failure of the mooring system on the leeward side mainly affects the surge, pitch and yaw response. Under the action of high-speed turbulent wind, the transient response of the platform is intensified; the drift distance of the sway is increased; the surge amplitude is increased. The maximum and average tension of the mooring system on the windward side are significantly increased, and the closer to the windward side, the greater the average tension of the mooring system. Therefore, the influence of high-speed turbulent wind should be considered in the design of platform mooring system for safety reasons.