In order to expand the floating wind turbine to shallow waters, the characteristics of the Spar platform is combined with the Semi platform and a new concept floating wind turbine platform is proposed suitable for the shallow waters of the South China Sea. The aerodynamic-hydrodynamic-anchor chain-elastic-servo coupling nonlinear dynamic analysis model of the floating wind turbine system is established. The leaf element-momentum theory is adopted to calculate the aerodynamic load. The hydrodynamic load is calculated based on the potential flow theory. The anchor chain tension is calculated based on the three-dimensional finite element method. Under the wind, wave and current environmental loads, the FAST software is used to study the motion response performance of the new concept floating wind turbine under different wind and wave angles. The results show that: the new concept floating platform supports a 6 MW wind turbine with a good motion response at a water depth of 50 m; there is no coupling between heave and pitch motion; the change of wave angle is of great influence on surge motion, and of certain influence on pitch, yaw and heave motion. The new concept floating wind machine is of good sport performance in the 50 m design waters of the South China Sea.