Abstract: Based on the characteristics of the deep-water floating photovoltaic platform in the practical engineering,a arrangement scheme plan is proposed,and a numerical calculation model of the photovoltaic platform and the mooring structure is established,and the accuracy of the calculation model is verified by comparison. According to the measured marine environment wind,wave,and current conditions,the full-time dynamic coupling calculation and analysis of the mooring structure for the floating photovoltaic platform are carried out to explore the motion response of the photovoltaic platform at six degrees of freedom and the tension response of the mooring structure under the extreme sea conditions in the 0°,45°,and 90° directions. The results show that the motions of the six degrees of freedom of the photovoltaic platform all respond the most when the maximum wave height occurs,and the surge motion in the 0°direction and the roll motion in the 90° direction are the most significant;in the directions of 0°,45°,and 90°,the mooring line tensions at the head sea side are the largest,and the tension responses of the mooring lines at the back swell are relatively small;when the tension responses of the mooring lines reach the maximum,the mooring lines in the direction of 0°,45°,and 90° are taut,the other mooring lines show the relaxation catenary linear,which preferably reflects the tension response of the mooring lines.