A floating combined cycle power plant includes a plurality of watertight bulkheads placed in a hull, having a structure suitable for being moved at sea, to the height of the freeboard deck; a power generating means for generating electricity, and a duct arranged to pass over the freeboard deck. The floating combined cycle power plant further includes: a fuel tank provided in the rear part of the hull and to supply the stored fuel to the power generating means; a carburetor unit provided in front of the fuel; and a loading unit provided in back of the fuel tank to receive fuel from a source and to store it in the fuel tank.