Abstract: A flotation system for an offshore power generation platform comprises: multiple buoyant bodies each containing a high-pressure air and ballast water therein to create buoyancy; connecting members connecting the multiple buoyant bodies to each other; ballast water flowing tubes through which the ballast water contained in the multiple buoyant bodies flows with respect to each other; a high-pressure tank supplying the high-pressure air into the multiple buoyant bodies; a compressor replenishing air pressure present in the high-pressure tank; an equilibrium sensor sensing an equilibrium state of each of the multiple buoyant bodies and transmitting a signal; and a controller controlling, in response to the signal from the equilibrium sensor, an amount of air supplied from the high-pressure tank to the buoyant body and an amount of air discharged from the buoyant body.