Provided are a floating structure fluid dynamic force use system and a wind-propelled vessel which uses the system whereby it is possible to compensate for overturning moment due to fluid dynamic force and to alleviate both tilting and size increases of a floating structure. A floating structure fluid dynamic force use system (1) comprises an assembly (12) which extracts energy from wind or water, and a floating structure (13) which supports the assembly (12). The assembly (12) comprises a wind receiving part (10) which receives fluid dynamic force, and a support column (11) which supports the wind receiving part (10). The assembly (12) is positioned with the center of gravity (15) thereof below the water line and is supported to be capable of tilting in an arbitrary direction upon the floating structure (13).